diff --git a/backend/add_tax_year_field.py b/backend/add_tax_year_field.py
new file mode 100644
index 0000000..7cbf8f2
--- /dev/null
+++ b/backend/add_tax_year_field.py
@@ -0,0 +1,43 @@
+import os
+import psycopg2
+from dotenv import load_dotenv
+
+load_dotenv()
+
+conn = psycopg2.connect(
+    host=os.getenv('DB_HOST'),
+    port=os.getenv('DB_PORT'),
+    dbname=os.getenv('DB_NAME'),
+    user=os.getenv('DB_USER'),
+    password=os.getenv('DB_PASSWORD')
+)
+
+cur = conn.cursor()
+
+# 年度フィールドを追加
+try:
+    cur.execute("ALTER TABLE income_tax_table ADD COLUMN tax_year INTEGER")
+    print("✓ tax_year カラムを追加")
+except Exception as e:
+    print(f"カラム追加スキップ（既に存在する可能性）: {e}")
+    conn.rollback()
+
+# 既存データに年度を設定
+try:
+    cur.execute("UPDATE income_tax_table SET tax_year = EXTRACT(YEAR FROM valid_from) WHERE tax_year IS NULL")
+    print("✓ 既存データに年度を設定")
+except Exception as e:
+    print(f"エラー: {e}")
+
+# インデックスを追加
+try:
+    cur.execute("CREATE INDEX IF NOT EXISTS idx_income_tax_year ON income_tax_table(tax_year)")
+    print("✓ インデックスを追加")
+except Exception as e:
+    print(f"インデックス追加エラー: {e}")
+
+conn.commit()
+cur.close()
+conn.close()
+
+print("\n完了！")
diff --git a/backend/app/main.py b/backend/app/main.py
index 553727d..1616c85 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -81,14 +81,40 @@ app.include_router(year_locks.router)
 from app.routers import cash
 app.include_router(cash.router)
 
+# ─────────────────────────
+# 給与モジュール (Payroll Module)
+# ─────────────────────────
+from app.payroll.employees.router import router as payroll_employees_router
+app.include_router(payroll_employees_router)
+
+from app.payroll.settings.router import router as payroll_settings_router
+app.include_router(payroll_settings_router)
+
+from app.payroll.calculation.router import router as payroll_calculation_router
+app.include_router(payroll_calculation_router)
+
+from app.payroll.bonus.router import router as payroll_bonus_router
+app.include_router(payroll_bonus_router)
+
 
 from fastapi.staticfiles import StaticFiles
+import os
 
-app.mount(
-    "/static",
-    StaticFiles(directory="app/static", html=True),
-    name="static",
-)
+# 静的ファイル配信（コメントアウト - ディレクトリが存在しない）
+# app.mount(
+#     "/static",
+#     StaticFiles(directory="app/static", html=True),
+#     name="static",
+# )
+
+# フロントエンドファイル配信（コメントアウト - file://プロトコルで直接アクセスするため不要）
+# frontend_path = os.path.join(os.path.dirname(os.path.dirname(os.path.dirname(__file__))), "frontend")
+# if os.path.exists(frontend_path):
+#     app.mount(
+#         "/",
+#         StaticFiles(directory=frontend_path, html=True),
+#         name="frontend",
+#     )
 
 
 
diff --git a/backend/app/payroll/__init__.py b/backend/app/payroll/__init__.py
new file mode 100644
index 0000000..d80ee17
--- /dev/null
+++ b/backend/app/payroll/__init__.py
@@ -0,0 +1,3 @@
+"""
+給与管理モジュール (Payroll Module)
+"""
diff --git a/backend/app/payroll/bonus/__init__.py b/backend/app/payroll/bonus/__init__.py
new file mode 100644
index 0000000..50b9161
--- /dev/null
+++ b/backend/app/payroll/bonus/__init__.py
@@ -0,0 +1 @@
+# Bonus Module
diff --git a/backend/app/payroll/bonus/router.py b/backend/app/payroll/bonus/router.py
new file mode 100644
index 0000000..4f1446d
--- /dev/null
+++ b/backend/app/payroll/bonus/router.py
@@ -0,0 +1,139 @@
+"""
+賞与計算API (Bonus Calculation API)
+"""
+from fastapi import APIRouter, HTTPException, status
+from typing import List
+from datetime import datetime
+from . import schemas
+from .service import BonusCalculationService
+from ...core.database import get_connection
+
+
+router = APIRouter(prefix="/payroll/bonus", tags=["Payroll - Bonus"])
+
+
+@router.post("/calculate", response_model=schemas.BonusPayment, status_code=status.HTTP_201_CREATED)
+def calculate_bonus(request: schemas.BonusCalculationRequest):
+    """賞与を計算"""
+    # 賞与を計算
+    calc_result = BonusCalculationService.calculate_bonus(
+        employee_id=request.employee_id,
+        bonus_year=request.bonus_year,
+        bonus_month=request.bonus_month,
+        bonus_type=request.bonus_type,
+        payment_date=request.payment_date,
+        base_bonus=request.base_bonus,
+        performance_bonus=request.performance_bonus,
+        other_bonus=request.other_bonus,
+        other_deduction=request.other_deduction,
+        calculated_by=request.calculated_by
+    )
+    
+    # データベースに保存
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO bonus_payments (
+                    employee_id, bonus_year, bonus_month, bonus_type, payment_date, status,
+                    base_bonus, performance_bonus, other_bonus, total_bonus,
+                    health_insurance, care_insurance, pension_insurance, employment_insurance,
+                    income_tax, other_deduction, total_deduction,
+                    net_bonus, calculated_at, calculated_by
+                ) VALUES (
+                    %s, %s, %s, %s, %s, %s,
+                    %s, %s, %s, %s,
+                    %s, %s, %s, %s,
+                    %s, %s, %s,
+                    %s, %s, %s
+                )
+                RETURNING *
+                """,
+                (
+                    calc_result["employee_id"], calc_result["bonus_year"], calc_result["bonus_month"],
+                    calc_result["bonus_type"], calc_result["payment_date"], calc_result["status"],
+                    calc_result["base_bonus"], calc_result["performance_bonus"], 
+                    calc_result["other_bonus"], calc_result["total_bonus"],
+                    calc_result["health_insurance"], calc_result["care_insurance"],
+                    calc_result["pension_insurance"], calc_result["employment_insurance"],
+                    calc_result["income_tax"], calc_result["other_deduction"],
+                    calc_result["total_deduction"],
+                    calc_result["net_bonus"], datetime.now(), calc_result["calculated_by"]
+                )
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/", response_model=List[schemas.BonusPayment])
+def get_bonuses(bonus_year: int = None, employee_id: int = None):
+    """賞与一覧を取得"""
+    conditions = []
+    params = []
+    
+    if bonus_year:
+        conditions.append("bonus_year = %s")
+        params.append(bonus_year)
+    
+    if employee_id:
+        conditions.append("employee_id = %s")
+        params.append(employee_id)
+    
+    where_clause = " AND ".join(conditions) if conditions else "1=1"
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"""
+                SELECT * FROM bonus_payments 
+                WHERE {where_clause}
+                ORDER BY bonus_year DESC, bonus_month DESC
+                """,
+                params
+            )
+            return cur.fetchall()
+
+
+@router.get("/{bonus_id}", response_model=schemas.BonusPayment)
+def get_bonus(bonus_id: int):
+    """賞与詳細を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("SELECT * FROM bonus_payments WHERE bonus_id = %s", (bonus_id,))
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="賞与が見つかりません")
+            return result
+
+
+@router.post("/{bonus_id}/approve", response_model=schemas.BonusPayment)
+def approve_bonus(bonus_id: int, approved_by: str):
+    """賞与を承認"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                UPDATE bonus_payments 
+                SET status = 'approved', approved_at = %s, approved_by = %s
+                WHERE bonus_id = %s AND status = 'calculated'
+                RETURNING *
+                """,
+                (datetime.now(), approved_by, bonus_id)
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="賞与が見つかりません、または既に承認済みです")
+            conn.commit()
+            return result
+
+
+@router.delete("/{bonus_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_bonus(bonus_id: int):
+    """賞与を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM bonus_payments WHERE bonus_id = %s AND status = 'draft'", (bonus_id,))
+            if cur.rowcount == 0:
+                raise HTTPException(status_code=404, detail="賞与が見つかりません、または削除できません")
+            conn.commit()
diff --git a/backend/app/payroll/bonus/schemas.py b/backend/app/payroll/bonus/schemas.py
new file mode 100644
index 0000000..ff7e4b8
--- /dev/null
+++ b/backend/app/payroll/bonus/schemas.py
@@ -0,0 +1,63 @@
+"""
+賞与計算のスキーマ定義 (Bonus Schemas)
+"""
+from pydantic import BaseModel
+from datetime import date, datetime
+from typing import Optional
+from decimal import Decimal
+
+
+class BonusPaymentBase(BaseModel):
+    """賞与計算基本情報"""
+    employee_id: int
+    bonus_year: int
+    bonus_month: int
+    bonus_type: str  # 夏季賞与/冬季賞与/決算賞与/その他
+    payment_date: date
+    base_bonus: Decimal = Decimal("0")
+    performance_bonus: Decimal = Decimal("0")
+    other_bonus: Decimal = Decimal("0")
+
+
+class BonusPaymentCreate(BonusPaymentBase):
+    """賞与計算の作成"""
+    pass
+
+
+class BonusCalculationRequest(BaseModel):
+    """賞与計算リクエスト"""
+    employee_id: int
+    bonus_year: int
+    bonus_month: int
+    bonus_type: str
+    payment_date: date
+    base_bonus: Decimal
+    performance_bonus: Decimal = Decimal("0")
+    other_bonus: Decimal = Decimal("0")
+    other_deduction: Decimal = Decimal("0")
+    calculated_by: str = "system"
+
+
+class BonusPayment(BonusPaymentBase):
+    """賞与計算結果"""
+    bonus_id: int
+    status: str
+    total_bonus: Decimal
+    health_insurance: Decimal
+    care_insurance: Decimal
+    pension_insurance: Decimal
+    employment_insurance: Decimal
+    income_tax: Decimal
+    other_deduction: Decimal
+    total_deduction: Decimal
+    net_bonus: Decimal
+    notes: Optional[str] = None
+    calculated_at: Optional[datetime] = None
+    calculated_by: Optional[str] = None
+    approved_at: Optional[datetime] = None
+    approved_by: Optional[str] = None
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
diff --git a/backend/app/payroll/bonus/service.py b/backend/app/payroll/bonus/service.py
new file mode 100644
index 0000000..198c59d
--- /dev/null
+++ b/backend/app/payroll/bonus/service.py
@@ -0,0 +1,235 @@
+"""
+賞与計算サービス (Bonus Calculation Service)
+"""
+from decimal import Decimal
+from datetime import date
+from typing import Dict, Any
+from ...core.database import get_connection
+
+
+class BonusCalculationService:
+    """賞与計算サービス"""
+    
+    @staticmethod
+    def get_insurance_rate(rate_type: str, target_date: date) -> Dict[str, Any]:
+        """保険料率を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT * FROM insurance_rates 
+                    WHERE rate_type = %s
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (rate_type, target_date, target_date)
+                )
+                return cur.fetchone()
+    
+    @staticmethod
+    def get_insurance_limit(setting_type: str, target_date: date) -> Decimal:
+        """社会保険料上限を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT limit_amount FROM insurance_limit_settings 
+                    WHERE setting_type = %s
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (setting_type, target_date, target_date)
+                )
+                result = cur.fetchone()
+                return Decimal(str(result["limit_amount"])) if result else Decimal("0")
+    
+    @staticmethod
+    def get_previous_salary_avg(employee_id: int, payment_date: date) -> Decimal:
+        """前月までの3ヶ月平均給与を取得（賞与所得税計算用）"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                # 前月までの3ヶ月の総支給額を取得
+                cur.execute(
+                    """
+                    SELECT AVG(total_payment - commute_allowance) as avg_salary
+                    FROM monthly_payroll 
+                    WHERE employee_id = %s
+                    AND payment_date < %s
+                    AND status IN ('approved', 'paid')
+                    ORDER BY payment_date DESC
+                    LIMIT 3
+                    """,
+                    (employee_id, payment_date)
+                )
+                result = cur.fetchone()
+                return Decimal(str(result["avg_salary"])) if result and result["avg_salary"] else Decimal("0")
+    
+    @staticmethod
+    def calculate_bonus_income_tax(
+        bonus_amount: Decimal,
+        previous_salary_avg: Decimal,
+        dependents_count: int
+    ) -> Decimal:
+        """
+        賞与所得税を計算
+        賞与税率 = (前月給与額 - 社会保険料) × 扶養人数に応じた税率
+        """
+        # 簡易計算: 賞与額から社会保険料概算を引いた額の10.21%を所得税とする
+        # 実際は前月給与から税率を求める複雑な計算が必要
+        if previous_salary_avg == Decimal("0"):
+            # 前月給与がない場合は賞与額の10.21%
+            return (bonus_amount * Decimal("0.1021")).quantize(Decimal("1"))
+        
+        # 扶養人数による税率軽減（簡略化）
+        rate = Decimal("0.1021")  # 基本税率 10.21%
+        if dependents_count == 1:
+            rate = Decimal("0.0820")  # 8.20%
+        elif dependents_count == 2:
+            rate = Decimal("0.0619")  # 6.19%
+        elif dependents_count >= 3:
+            rate = Decimal("0.0418")  # 4.18%
+        
+        return (bonus_amount * rate).quantize(Decimal("1"))
+    
+    @staticmethod
+    def calculate_bonus(
+        employee_id: int,
+        bonus_year: int,
+        bonus_month: int,
+        bonus_type: str,
+        payment_date: date,
+        base_bonus: Decimal,
+        performance_bonus: Decimal = Decimal("0"),
+        other_bonus: Decimal = Decimal("0"),
+        other_deduction: Decimal = Decimal("0"),
+        calculated_by: str = "system"
+    ) -> Dict[str, Any]:
+        """賞与を計算"""
+        
+        # 総支給額
+        total_bonus = base_bonus + performance_bonus + other_bonus
+        
+        # 社会保険料上限を取得
+        health_insurance_limit = BonusCalculationService.get_insurance_limit(
+            "健康保険標準報酬月額上限", payment_date
+        )
+        pension_insurance_limit = BonusCalculationService.get_insurance_limit(
+            "厚生年金標準報酬月額上限", payment_date
+        )
+        
+        # 賞与の標準賞与額（上限適用）
+        health_standard_bonus = min(total_bonus, health_insurance_limit) if health_insurance_limit > 0 else total_bonus
+        pension_standard_bonus = min(total_bonus, pension_insurance_limit) if pension_insurance_limit > 0 else total_bonus
+        
+        # 従業員情報を取得（年齢計算のため）
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    "SELECT birth_date FROM employees WHERE employee_id = %s",
+                    (employee_id,)
+                )
+                employee_info = cur.fetchone()
+        
+        # 年齢を計算
+        age = 0
+        if employee_info and employee_info["birth_date"]:
+            age = (payment_date - employee_info["birth_date"]).days // 365
+        
+        # 健康保険（賞与額の1/1000で計算）
+        health_insurance_rate = BonusCalculationService.get_insurance_rate("健康保険", payment_date)
+        health_insurance = Decimal("0")
+        if health_insurance_rate:
+            health_insurance = (
+                health_standard_bonus * Decimal(str(health_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 介護保険（40歳以上65歳未満が対象）
+        care_insurance = Decimal("0")
+        if 40 <= age < 65:
+            care_insurance_rate = BonusCalculationService.get_insurance_rate("介護保険", payment_date)
+            if care_insurance_rate:
+                care_insurance = (
+                    health_standard_bonus * Decimal(str(care_insurance_rate["employee_rate"]))
+                ).quantize(Decimal("1"))
+        
+        # 厚生年金
+        pension_insurance_rate = BonusCalculationService.get_insurance_rate("厚生年金", payment_date)
+        pension_insurance = Decimal("0")
+        if pension_insurance_rate:
+            pension_insurance = (
+                pension_standard_bonus * Decimal(str(pension_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 雇用保険
+        employment_insurance_rate = BonusCalculationService.get_insurance_rate("雇用保険", payment_date)
+        employment_insurance = Decimal("0")
+        if employment_insurance_rate:
+            employment_insurance = (
+                total_bonus * Decimal(str(employment_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 所得税の計算（賞与特有の計算）
+        from ..calculation.service import PayrollCalculationService
+        dependents_count = PayrollCalculationService.get_active_dependents_count(employee_id, payment_date)
+        previous_salary_avg = BonusCalculationService.get_previous_salary_avg(employee_id, payment_date)
+        
+        # 課税対象額
+        taxable_bonus = (
+            total_bonus - 
+            health_insurance - 
+            care_insurance -
+            pension_insurance - 
+            employment_insurance
+        )
+        
+        income_tax = BonusCalculationService.calculate_bonus_income_tax(
+            taxable_bonus,
+            previous_salary_avg,
+            dependents_count
+        )
+        
+        # 総控除額
+        total_deduction = (
+            health_insurance + 
+            care_insurance +
+            pension_insurance + 
+            employment_insurance + 
+            income_tax + 
+            other_deduction
+        )
+        
+        # 差引支給額
+        net_bonus = total_bonus - total_deduction
+        
+        return {
+            "employee_id": employee_id,
+            "bonus_year": bonus_year,
+            "bonus_month": bonus_month,
+            "bonus_type": bonus_type,
+            "payment_date": payment_date,
+            "status": "calculated",
+            
+            # 支給項目
+            "base_bonus": base_bonus,
+            "performance_bonus": performance_bonus,
+            "other_bonus": other_bonus,
+            "total_bonus": total_bonus,
+            
+            # 控除項目
+            "health_insurance": health_insurance,
+            "care_insurance": care_insurance,
+            "pension_insurance": pension_insurance,
+            "employment_insurance": employment_insurance,
+            "income_tax": income_tax,
+            "other_deduction": other_deduction,
+            "total_deduction": total_deduction,
+            
+            # 差引支給額
+            "net_bonus": net_bonus,
+            
+            "calculated_by": calculated_by
+        }
diff --git a/backend/app/payroll/calculation/__init__.py b/backend/app/payroll/calculation/__init__.py
new file mode 100644
index 0000000..084a561
--- /dev/null
+++ b/backend/app/payroll/calculation/__init__.py
@@ -0,0 +1,3 @@
+"""
+月次給与計算 (Monthly Payroll Calculation)
+"""
diff --git a/backend/app/payroll/calculation/router.py b/backend/app/payroll/calculation/router.py
new file mode 100644
index 0000000..fedc8e8
--- /dev/null
+++ b/backend/app/payroll/calculation/router.py
@@ -0,0 +1,284 @@
+"""
+月次給与計算API (Monthly Payroll Calculation API)
+"""
+from fastapi import APIRouter, HTTPException, status
+from typing import List
+from datetime import datetime
+from . import schemas
+from .service import PayrollCalculationService
+from ...core.database import get_connection
+
+
+router = APIRouter(prefix="/payroll/calculation", tags=["Payroll - Calculation"])
+
+
+@router.post("/calculate", response_model=schemas.MonthlyPayroll, status_code=status.HTTP_201_CREATED)
+def calculate_payroll(request: schemas.PayrollCalculationRequest):
+    """給与を計算して保存"""
+    
+    # 既存のデータを確認
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT payroll_id FROM monthly_payroll 
+                WHERE employee_id = %s 
+                AND payroll_year = %s 
+                AND payroll_month = %s
+                """,
+                (request.employee_id, request.payroll_year, request.payroll_month)
+            )
+            existing = cur.fetchone()
+            
+            if existing:
+                raise HTTPException(
+                    status_code=400, 
+                    detail="この従業員の指定月の給与データは既に存在します"
+                )
+    
+    # 給与計算を実行
+    try:
+        calc_result = PayrollCalculationService.calculate_payroll(
+            employee_id=request.employee_id,
+            payroll_year=request.payroll_year,
+            payroll_month=request.payroll_month,
+            working_days=request.working_days,
+            working_hours=request.working_hours,
+            overtime_hours=request.overtime_hours,
+            holiday_hours=request.holiday_hours,
+            late_hours=request.late_hours,
+            absent_days=request.absent_days,
+            payment_date=request.payment_date,
+            other_allowance=request.other_allowance,
+            resident_tax=request.resident_tax,
+            other_deduction=request.other_deduction
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    
+    # 結果をデータベースに保存
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO monthly_payroll (
+                    employee_id, payroll_year, payroll_month, payment_date, status,
+                    working_days, working_hours, overtime_hours, holiday_hours, late_hours, absent_days,
+                    base_salary, overtime_pay, holiday_pay, commute_allowance, other_allowance, total_payment,
+                    health_insurance, care_insurance, pension_insurance, employment_insurance, 
+                    income_tax, resident_tax, other_deduction, total_deduction,
+                    net_payment, calculated_at, calculated_by
+                ) VALUES (
+                    %s, %s, %s, %s, %s,
+                    %s, %s, %s, %s, %s, %s,
+                    %s, %s, %s, %s, %s, %s,
+                    %s, %s, %s, %s,
+                    %s, %s, %s, %s,
+                    %s, %s, %s
+                )
+                RETURNING *
+                """,
+                (
+                    calc_result["employee_id"], calc_result["payroll_year"], calc_result["payroll_month"],
+                    calc_result["payment_date"], calc_result["status"],
+                    calc_result["working_days"], calc_result["working_hours"], calc_result["overtime_hours"],
+                    calc_result["holiday_hours"], calc_result["late_hours"], calc_result["absent_days"],
+                    calc_result["base_salary"], calc_result["overtime_pay"], calc_result["holiday_pay"],
+                    calc_result["commute_allowance"], calc_result["other_allowance"], calc_result["total_payment"],
+                    calc_result["health_insurance"], calc_result["care_insurance"], 
+                    calc_result["pension_insurance"], calc_result["employment_insurance"],
+                    calc_result["income_tax"], calc_result["resident_tax"], calc_result["other_deduction"],
+                    calc_result["total_deduction"],
+                    calc_result["net_payment"], datetime.now(), calc_result["calculated_by"]
+                )
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/", response_model=List[schemas.MonthlyPayroll])
+def get_payrolls(payroll_year: int = None, payroll_month: int = None, employee_id: int = None):
+    """給与計算一覧を取得"""
+    conditions = []
+    params = []
+    
+    if payroll_year:
+        conditions.append("payroll_year = %s")
+        params.append(payroll_year)
+    
+    if payroll_month:
+        conditions.append("payroll_month = %s")
+        params.append(payroll_month)
+    
+    if employee_id:
+        conditions.append("employee_id = %s")
+        params.append(employee_id)
+    
+    where_clause = " AND ".join(conditions) if conditions else "1=1"
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"""
+                SELECT * FROM monthly_payroll 
+                WHERE {where_clause}
+                ORDER BY payroll_year DESC, payroll_month DESC, employee_id
+                """,
+                params
+            )
+            return cur.fetchall()
+
+
+@router.get("/{payroll_id}", response_model=schemas.MonthlyPayrollWithDetails)
+def get_payroll(payroll_id: int):
+    """給与計算詳細を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("SELECT * FROM monthly_payroll WHERE payroll_id = %s", (payroll_id,))
+            payroll = cur.fetchone()
+            
+            if not payroll:
+                raise HTTPException(status_code=404, detail="給与データが見つかりません")
+            
+            cur.execute(
+                "SELECT * FROM payroll_details WHERE payroll_id = %s ORDER BY detail_id",
+                (payroll_id,)
+            )
+            details = cur.fetchall()
+            
+            return {**payroll, "details": details}
+
+
+@router.put("/{payroll_id}", response_model=schemas.MonthlyPayroll)
+def update_payroll(payroll_id: int, request: schemas.MonthlyPayrollUpdate):
+    """給与データを更新（再計算は行わない）"""
+    update_data = request.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [payroll_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE monthly_payroll SET {set_clause} WHERE payroll_id = %s RETURNING *",
+                values,
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="給与データが見つかりません")
+            conn.commit()
+            return result
+
+
+@router.post("/{payroll_id}/recalculate", response_model=schemas.MonthlyPayroll)
+def recalculate_payroll(payroll_id: int):
+    """給与を再計算"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # 既存データを取得
+            cur.execute("SELECT * FROM monthly_payroll WHERE payroll_id = %s", (payroll_id,))
+            existing = cur.fetchone()
+            
+            if not existing:
+                raise HTTPException(status_code=404, detail="給与データが見つかりません")
+            
+            if existing["status"] == "approved":
+                raise HTTPException(status_code=400, detail="承認済みの給与は再計算できません")
+            
+            # 再計算
+            try:
+                calc_result = PayrollCalculationService.calculate_payroll(
+                    employee_id=existing["employee_id"],
+                    payroll_year=existing["payroll_year"],
+                    payroll_month=existing["payroll_month"],
+                    working_days=existing["working_days"],
+                    working_hours=existing["working_hours"],
+                    overtime_hours=existing["overtime_hours"],
+                    holiday_hours=existing["holiday_hours"],
+                    late_hours=existing["late_hours"],
+                    absent_days=existing["absent_days"],
+                    payment_date=existing["payment_date"],
+                    other_allowance=existing["other_allowance"],
+                    resident_tax=existing["resident_tax"],
+                    other_deduction=existing["other_deduction"],
+                    calculated_by="recalculated"
+                )
+            except ValueError as e:
+                raise HTTPException(status_code=400, detail=str(e))
+            
+            # 更新
+            cur.execute(
+                """
+                UPDATE monthly_payroll SET
+                    base_salary = %s, overtime_pay = %s, holiday_pay = %s,
+                    commute_allowance = %s, total_payment = %s,
+                    health_insurance = %s, pension_insurance = %s, employment_insurance = %s,
+                    income_tax = %s, total_deduction = %s, net_payment = %s,
+                    calculated_at = %s, calculated_by = %s
+                WHERE payroll_id = %s
+                RETURNING *
+                """,
+                (
+                    calc_result["base_salary"], calc_result["overtime_pay"], calc_result["holiday_pay"],
+                    calc_result["commute_allowance"], calc_result["total_payment"],
+                    calc_result["health_insurance"], calc_result["pension_insurance"], 
+                    calc_result["employment_insurance"],
+                    calc_result["income_tax"], calc_result["total_deduction"], calc_result["net_payment"],
+                    datetime.now(), calc_result["calculated_by"],
+                    payroll_id
+                )
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.post("/{payroll_id}/approve", response_model=schemas.MonthlyPayroll)
+def approve_payroll(payroll_id: int, request: schemas.PayrollApprovalRequest):
+    """給与を承認"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                UPDATE monthly_payroll 
+                SET status = 'approved', approved_at = %s, approved_by = %s
+                WHERE payroll_id = %s AND status = 'calculated'
+                RETURNING *
+                """,
+                (datetime.now(), request.approved_by, payroll_id)
+            )
+            result = cur.fetchone()
+            
+            if not result:
+                raise HTTPException(
+                    status_code=400, 
+                    detail="給与データが見つからないか、既に承認されています"
+                )
+            
+            conn.commit()
+            return result
+
+
+@router.delete("/{payroll_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_payroll(payroll_id: int):
+    """給与データを削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # ステータス確認
+            cur.execute(
+                "SELECT status FROM monthly_payroll WHERE payroll_id = %s",
+                (payroll_id,)
+            )
+            payroll = cur.fetchone()
+            
+            if not payroll:
+                raise HTTPException(status_code=404, detail="給与データが見つかりません")
+            
+            if payroll["status"] == "approved":
+                raise HTTPException(status_code=400, detail="承認済みの給与は削除できません")
+            
+            cur.execute("DELETE FROM monthly_payroll WHERE payroll_id = %s", (payroll_id,))
+            conn.commit()
diff --git a/backend/app/payroll/calculation/schemas.py b/backend/app/payroll/calculation/schemas.py
new file mode 100644
index 0000000..00e4ec9
--- /dev/null
+++ b/backend/app/payroll/calculation/schemas.py
@@ -0,0 +1,129 @@
+"""
+月次給与計算のスキーマ定義 (Payroll Calculation Schemas)
+"""
+from pydantic import BaseModel
+from datetime import date, datetime
+from typing import Optional
+from decimal import Decimal
+
+
+class PayrollDetailBase(BaseModel):
+    """給与明細項目"""
+    item_type: str  # payment/deduction
+    item_code: str
+    item_name: str
+    amount: Decimal
+    notes: Optional[str] = None
+
+
+class PayrollDetailCreate(PayrollDetailBase):
+    """給与明細項目の作成"""
+    pass
+
+
+class PayrollDetail(PayrollDetailBase):
+    """給与明細項目の情報"""
+    detail_id: int
+    payroll_id: int
+    created_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class MonthlyPayrollBase(BaseModel):
+    """月次給与計算の基本情報"""
+    employee_id: int
+    payroll_year: int
+    payroll_month: int
+    payment_date: date
+    
+    # 勤怠情報
+    working_days: Decimal = Decimal("0")
+    working_hours: Decimal = Decimal("0")
+    overtime_hours: Decimal = Decimal("0")
+    holiday_hours: Decimal = Decimal("0")
+    late_hours: Decimal = Decimal("0")
+    absent_days: Decimal = Decimal("0")
+    
+    notes: Optional[str] = None
+
+
+class MonthlyPayrollCreate(MonthlyPayrollBase):
+    """月次給与計算の作成"""
+    pass
+
+
+class MonthlyPayrollUpdate(BaseModel):
+    """月次給与計算の更新"""
+    payment_date: Optional[date] = None
+    working_days: Optional[Decimal] = None
+    working_hours: Optional[Decimal] = None
+    overtime_hours: Optional[Decimal] = None
+    holiday_hours: Optional[Decimal] = None
+    late_hours: Optional[Decimal] = None
+    absent_days: Optional[Decimal] = None
+    notes: Optional[str] = None
+
+
+class MonthlyPayroll(MonthlyPayrollBase):
+    """月次給与計算の情報"""
+    payroll_id: int
+    status: str
+    
+    # 支給項目
+    base_salary: Decimal
+    overtime_pay: Decimal
+    holiday_pay: Decimal
+    commute_allowance: Decimal
+    other_allowance: Decimal
+    total_payment: Decimal
+    
+    # 控除項目
+    health_insurance: Decimal
+    pension_insurance: Decimal
+    employment_insurance: Decimal
+    income_tax: Decimal
+    resident_tax: Decimal
+    other_deduction: Decimal
+    total_deduction: Decimal
+    
+    # 差引支給額
+    net_payment: Decimal
+    
+    calculated_at: Optional[datetime] = None
+    calculated_by: Optional[str] = None
+    approved_at: Optional[datetime] = None
+    approved_by: Optional[str] = None
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class MonthlyPayrollWithDetails(MonthlyPayroll):
+    """明細項目を含む月次給与情報"""
+    details: list[PayrollDetail] = []
+
+
+class PayrollCalculationRequest(BaseModel):
+    """給与計算リクエスト"""
+    employee_id: int
+    payroll_year: int
+    payroll_month: int
+    working_days: Decimal = Decimal("0")
+    working_hours: Decimal = Decimal("0")
+    overtime_hours: Decimal = Decimal("0")
+    holiday_hours: Decimal = Decimal("0")
+    late_hours: Decimal = Decimal("0")
+    absent_days: Decimal = Decimal("0")
+    payment_date: date
+    other_allowance: Decimal = Decimal("0")
+    resident_tax: Decimal = Decimal("0")
+    other_deduction: Decimal = Decimal("0")
+
+
+class PayrollApprovalRequest(BaseModel):
+    """給与承認リクエスト"""
+    approved_by: str
diff --git a/backend/app/payroll/calculation/service.py b/backend/app/payroll/calculation/service.py
new file mode 100644
index 0000000..d9128b0
--- /dev/null
+++ b/backend/app/payroll/calculation/service.py
@@ -0,0 +1,317 @@
+"""
+給与計算サービス (Payroll Calculation Service)
+"""
+from decimal import Decimal
+from datetime import date
+from typing import Dict, Any
+from ...core.database import get_connection
+
+
+class PayrollCalculationService:
+    """給与計算サービス"""
+    
+    @staticmethod
+    def get_active_dependents_count(employee_id: int, target_date: date) -> int:
+        """有効な扶養家族数を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT COUNT(*) as count FROM dependents 
+                    WHERE employee_id = %s
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    """,
+                    (employee_id, target_date, target_date)
+                )
+                result = cur.fetchone()
+                return result["count"] if result else 0
+    
+    @staticmethod
+    def get_salary_setting(employee_id: int, target_date: date) -> Dict[str, Any]:
+        """給与設定を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT * FROM salary_settings 
+                    WHERE employee_id = %s 
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (employee_id, target_date, target_date)
+                )
+                return cur.fetchone()
+    
+    @staticmethod
+    def get_insurance_rate(rate_type: str, target_date: date) -> Dict[str, Any]:
+        """保険料率を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT * FROM insurance_rates 
+                    WHERE rate_type = %s
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (rate_type, target_date, target_date)
+                )
+                return cur.fetchone()
+    
+    @staticmethod
+    def get_insurance_limit(setting_type: str, target_date: date) -> Decimal:
+        """社会保険料上限を取得"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT limit_amount FROM insurance_limit_settings 
+                    WHERE setting_type = %s
+                    AND valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (setting_type, target_date, target_date)
+                )
+                result = cur.fetchone()
+                return Decimal(str(result["limit_amount"])) if result else Decimal("0")
+    
+    @staticmethod
+    def calculate_income_tax(
+        monthly_income: Decimal, 
+        dependents_count: int, 
+        target_date: date
+    ) -> Decimal:
+        """所得税を計算"""
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    """
+                    SELECT tax_amount FROM income_tax_table 
+                    WHERE valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    AND dependents_count = %s
+                    AND monthly_income_from <= %s
+                    AND monthly_income_to >= %s
+                    ORDER BY valid_from DESC
+                    LIMIT 1
+                    """,
+                    (target_date, target_date, dependents_count, monthly_income, monthly_income)
+                )
+                result = cur.fetchone()
+                return Decimal(str(result["tax_amount"])) if result else Decimal("0")
+    
+    @staticmethod
+    def calculate_payroll(
+        employee_id: int,
+        payroll_year: int,
+        payroll_month: int,
+        working_days: Decimal,
+        working_hours: Decimal,
+        overtime_hours: Decimal,
+        holiday_hours: Decimal,
+        late_hours: Decimal,
+        absent_days: Decimal,
+        payment_date: date,
+        other_allowance: Decimal = Decimal("0"),
+        resident_tax: Decimal = Decimal("0"),
+        other_deduction: Decimal = Decimal("0"),
+        calculated_by: str = "system"
+    ) -> Dict[str, Any]:
+        """給与を計算"""
+        
+        # 給与設定を取得
+        salary_setting = PayrollCalculationService.get_salary_setting(employee_id, payment_date)
+        if not salary_setting:
+            raise ValueError("給与設定が見つかりません")
+        
+        # 基本給の計算
+        base_salary = Decimal(str(salary_setting["base_salary"]))
+        
+        # 時給の場合は勤務時間から計算
+        if salary_setting["payment_type"] == "時給" and salary_setting["hourly_rate"]:
+            hourly_rate = Decimal(str(salary_setting["hourly_rate"]))
+            base_salary = hourly_rate * working_hours
+        
+        # 欠勤控除（日給制の場合）
+        absence_deduction = Decimal("0")
+        if absent_days > 0 and salary_setting["payment_type"] == "月給":
+            # 月給を営業日数で割って欠勤日数を掛ける（簡易計算）
+            daily_rate = base_salary / Decimal("22")  # 月平均営業日数を22日と仮定
+            absence_deduction = daily_rate * absent_days
+            base_salary = base_salary - absence_deduction
+        
+        # 残業手当の計算（時給 × 1.25）
+        overtime_pay = Decimal("0")
+        if overtime_hours > 0:
+            if salary_setting["hourly_rate"]:
+                hourly_rate = Decimal(str(salary_setting["hourly_rate"]))
+            else:
+                # 月給を時給に換算（月平均労働時間を160時間と仮定）
+                hourly_rate = Decimal(str(salary_setting["base_salary"])) / Decimal("160")
+            overtime_pay = hourly_rate * overtime_hours * Decimal("1.25")
+        
+        # 休日手当の計算（時給 × 1.35）
+        holiday_pay = Decimal("0")
+        if holiday_hours > 0:
+            if salary_setting["hourly_rate"]:
+                hourly_rate = Decimal(str(salary_setting["hourly_rate"]))
+            else:
+                hourly_rate = Decimal(str(salary_setting["base_salary"])) / Decimal("160")
+            holiday_pay = hourly_rate * holiday_hours * Decimal("1.35")
+        
+        # 通勤手当
+        commute_allowance = Decimal(str(salary_setting["commute_allowance"]))
+        
+        # 総支給額
+        total_payment = (
+            base_salary + overtime_pay + holiday_pay + 
+            commute_allowance + other_allowance
+        )
+        
+        # 社会保険料の計算（標準報酬月額を総支給額と仮定）
+        standard_monthly_salary = total_payment
+        
+        # 社会保険料上限を取得
+        health_insurance_limit = PayrollCalculationService.get_insurance_limit(
+            "健康保険標準報酬月額上限", payment_date
+        )
+        pension_insurance_limit = PayrollCalculationService.get_insurance_limit(
+            "厚生年金標準報酬月額上限", payment_date
+        )
+        commute_tax_free_limit = PayrollCalculationService.get_insurance_limit(
+            "通勤手当非課税限度額", payment_date
+        )
+        
+        # 標準報酬月額に上限を適用
+        health_standard_salary = min(standard_monthly_salary, health_insurance_limit) if health_insurance_limit > 0 else standard_monthly_salary
+        pension_standard_salary = min(standard_monthly_salary, pension_insurance_limit) if pension_insurance_limit > 0 else standard_monthly_salary
+        
+        # 従業員情報を取得（年齢計算のため）
+        with get_connection() as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    "SELECT birth_date FROM employees WHERE employee_id = %s",
+                    (employee_id,)
+                )
+                employee_info = cur.fetchone()
+        
+        # 年齢を計算（介護保険は40歳以上が対象）
+        age = 0
+        if employee_info and employee_info["birth_date"]:
+            age = (payment_date - employee_info["birth_date"]).days // 365
+        
+        # 健康保険（上限適用後の標準報酬月額で計算）
+        health_insurance_rate = PayrollCalculationService.get_insurance_rate("健康保険", payment_date)
+        health_insurance = Decimal("0")
+        if health_insurance_rate:
+            health_insurance = (
+                health_standard_salary * Decimal(str(health_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 介護保険（40歳以上65歳未満が対象、健康保険と同じ標準報酬月額）
+        care_insurance = Decimal("0")
+        if 40 <= age < 65:
+            care_insurance_rate = PayrollCalculationService.get_insurance_rate("介護保険", payment_date)
+            if care_insurance_rate:
+                care_insurance = (
+                    health_standard_salary * Decimal(str(care_insurance_rate["employee_rate"]))
+                ).quantize(Decimal("1"))
+        
+        # 厚生年金（上限適用後の標準報酬月額で計算）
+        pension_insurance_rate = PayrollCalculationService.get_insurance_rate("厚生年金", payment_date)
+        pension_insurance = Decimal("0")
+        if pension_insurance_rate:
+            pension_insurance = (
+                pension_standard_salary * Decimal(str(pension_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 雇用保険
+        employment_insurance_rate = PayrollCalculationService.get_insurance_rate("雇用保険", payment_date)
+        employment_insurance = Decimal("0")
+        if employment_insurance_rate:
+            employment_insurance = (
+                total_payment * Decimal(str(employment_insurance_rate["employee_rate"]))
+            ).quantize(Decimal("1"))
+        
+        # 所得税の計算
+        dependents_count = PayrollCalculationService.get_active_dependents_count(employee_id, payment_date)
+        
+        # 通勤手当非課税限度額を取得（設定がなければ150000円）
+        if commute_tax_free_limit == Decimal("0"):
+            commute_tax_free_limit = Decimal("150000")
+        
+        # 課税対象額 = 総支給額 - 通勤手当（非課税限度額まで） - 社会保険料
+        taxable_income = (
+            total_payment - 
+            min(commute_allowance, commute_tax_free_limit) - 
+            health_insurance - 
+            care_insurance -
+            pension_insurance - 
+            employment_insurance
+        )
+        
+        income_tax = PayrollCalculationService.calculate_income_tax(
+            taxable_income, 
+            dependents_count, 
+            payment_date
+        )
+        
+        # 総控除額
+        total_deduction = (
+            health_insurance + 
+            care_insurance +
+            pension_insurance + 
+            employment_insurance + 
+            income_tax + 
+            resident_tax + 
+            other_deduction
+        )
+        
+        # 差引支給額
+        net_payment = total_payment - total_deduction
+        
+        return {
+            "employee_id": employee_id,
+            "payroll_year": payroll_year,
+            "payroll_month": payroll_month,
+            "payment_date": payment_date,
+            "status": "calculated",
+            
+            # 勤怠情報
+            "working_days": working_days,
+            "working_hours": working_hours,
+            "overtime_hours": overtime_hours,
+            "holiday_hours": holiday_hours,
+            "late_hours": late_hours,
+            "absent_days": absent_days,
+            
+            # 支給項目
+            "base_salary": base_salary,
+            "overtime_pay": overtime_pay,
+            "holiday_pay": holiday_pay,
+            "commute_allowance": commute_allowance,
+            "other_allowance": other_allowance,
+            "total_payment": total_payment,
+            
+            # 控除項目
+            "health_insurance": health_insurance,
+            "care_insurance": care_insurance,
+            "pension_insurance": pension_insurance,
+            "employment_insurance": employment_insurance,
+            "income_tax": income_tax,
+            "resident_tax": resident_tax,
+            "other_deduction": other_deduction,
+            "total_deduction": total_deduction,
+            
+            # 差引支給額
+            "net_payment": net_payment,
+            
+            "calculated_by": calculated_by
+        }
diff --git a/backend/app/payroll/employees/__init__.py b/backend/app/payroll/employees/__init__.py
new file mode 100644
index 0000000..a4950de
--- /dev/null
+++ b/backend/app/payroll/employees/__init__.py
@@ -0,0 +1,3 @@
+"""
+従業員管理 (Employee Management)
+"""
diff --git a/backend/app/payroll/employees/router.py b/backend/app/payroll/employees/router.py
new file mode 100644
index 0000000..f2a3fe1
--- /dev/null
+++ b/backend/app/payroll/employees/router.py
@@ -0,0 +1,196 @@
+"""
+従業員管理API (Employee Management API)
+"""
+from fastapi import APIRouter, HTTPException, status
+from typing import List
+from . import schemas
+from ...core.database import get_connection
+
+
+router = APIRouter(prefix="/payroll/employees", tags=["Payroll - Employees"])
+
+
+@router.post("/", response_model=schemas.Employee, status_code=status.HTTP_201_CREATED)
+def create_employee(employee: schemas.EmployeeCreate):
+    """従業員を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO employees (
+                    employee_code, name, name_kana, birth_date, gender,
+                    email, phone, postal_code, address, hire_date, termination_date, is_active,
+                    bank_name, bank_branch, bank_account_number, bank_account_type, notes
+                ) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (
+                    employee.employee_code, employee.name, employee.name_kana,
+                    employee.birth_date, employee.gender,
+                    employee.email, employee.phone, employee.postal_code, employee.address,
+                    employee.hire_date, employee.termination_date, employee.is_active,
+                    employee.bank_name, employee.bank_branch,
+                    employee.bank_account_number, employee.bank_account_type, employee.notes
+                ),
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/", response_model=List[schemas.Employee])
+def get_employees(is_active: bool = None):
+    """従業員一覧を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            if is_active is not None:
+                cur.execute(
+                    "SELECT * FROM employees WHERE is_active = %s ORDER BY employee_code",
+                    (is_active,)
+                )
+            else:
+                cur.execute("SELECT * FROM employees ORDER BY employee_code")
+            return cur.fetchall()
+
+
+@router.get("/{employee_id}", response_model=schemas.EmployeeWithDependents)
+def get_employee(employee_id: int):
+    """従業員の詳細を取得（扶養家族を含む）"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # 従業員情報取得
+            cur.execute("SELECT * FROM employees WHERE employee_id = %s", (employee_id,))
+            employee = cur.fetchone()
+            if not employee:
+                raise HTTPException(status_code=404, detail="従業員が見つかりません")
+            
+            # 扶養家族情報取得
+            cur.execute(
+                """
+                SELECT * FROM dependents 
+                WHERE employee_id = %s 
+                AND (valid_to IS NULL OR valid_to >= CURRENT_DATE)
+                ORDER BY valid_from
+                """,
+                (employee_id,)
+            )
+            dependents = cur.fetchall()
+            
+            return {**employee, "dependents": dependents}
+
+
+@router.put("/{employee_id}", response_model=schemas.Employee)
+def update_employee(employee_id: int, employee: schemas.EmployeeUpdate):
+    """従業員情報を更新"""
+    update_data = employee.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [employee_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE employees SET {set_clause} WHERE employee_id = %s RETURNING *",
+                values,
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="従業員が見つかりません")
+            conn.commit()
+            return result
+
+
+@router.delete("/{employee_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_employee(employee_id: int):
+    """従業員を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM employees WHERE employee_id = %s", (employee_id,))
+            if cur.rowcount == 0:
+                raise HTTPException(status_code=404, detail="従業員が見つかりません")
+            conn.commit()
+
+
+# ========================================
+# 扶養家族管理
+# ========================================
+
+@router.post("/{employee_id}/dependents", response_model=schemas.Dependent, status_code=status.HTTP_201_CREATED)
+def create_dependent(employee_id: int, dependent: schemas.DependentCreate):
+    """扶養家族を追加"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # 従業員の存在確認
+            cur.execute("SELECT employee_id FROM employees WHERE employee_id = %s", (employee_id,))
+            if not cur.fetchone():
+                raise HTTPException(status_code=404, detail="従業員が見つかりません")
+            
+            cur.execute(
+                """
+                INSERT INTO dependents (
+                    employee_id, name, relationship, birth_date,
+                    is_spouse, is_disabled, income_amount, valid_from, valid_to
+                ) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (
+                    employee_id, dependent.name, dependent.relationship, dependent.birth_date,
+                    dependent.is_spouse, dependent.is_disabled, dependent.income_amount,
+                    dependent.valid_from, dependent.valid_to
+                ),
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/{employee_id}/dependents", response_model=List[schemas.Dependent])
+def get_dependents(employee_id: int):
+    """従業員の扶養家族一覧を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM dependents 
+                WHERE employee_id = %s 
+                ORDER BY valid_from DESC
+                """,
+                (employee_id,)
+            )
+            return cur.fetchall()
+
+
+@router.put("/dependents/{dependent_id}", response_model=schemas.Dependent)
+def update_dependent(dependent_id: int, dependent: schemas.DependentUpdate):
+    """扶養家族情報を更新"""
+    update_data = dependent.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [dependent_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE dependents SET {set_clause} WHERE dependent_id = %s RETURNING *",
+                values,
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="扶養家族が見つかりません")
+            conn.commit()
+            return result
+
+
+@router.delete("/dependents/{dependent_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_dependent(dependent_id: int):
+    """扶養家族を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM dependents WHERE dependent_id = %s", (dependent_id,))
+            if cur.rowcount == 0:
+                raise HTTPException(status_code=404, detail="扶養家族が見つかりません")
+            conn.commit()
diff --git a/backend/app/payroll/employees/schemas.py b/backend/app/payroll/employees/schemas.py
new file mode 100644
index 0000000..5edda0e
--- /dev/null
+++ b/backend/app/payroll/employees/schemas.py
@@ -0,0 +1,109 @@
+"""
+従業員管理用のスキーマ定義 (Employee Schemas)
+"""
+from pydantic import BaseModel, EmailStr
+from datetime import date, datetime
+from typing import Optional
+from decimal import Decimal
+
+
+class DependentBase(BaseModel):
+    """扶養家族の基本情報"""
+    name: str
+    relationship: str  # 配偶者/子/親/その他
+    birth_date: Optional[date] = None
+    is_spouse: bool = False
+    is_disabled: bool = False
+    income_amount: Decimal = Decimal("0")
+    valid_from: date
+    valid_to: Optional[date] = None
+
+
+class DependentCreate(DependentBase):
+    """扶養家族の作成"""
+    pass
+
+
+class DependentUpdate(BaseModel):
+    """扶養家族の更新"""
+    name: Optional[str] = None
+    relationship: Optional[str] = None
+    birth_date: Optional[date] = None
+    is_spouse: Optional[bool] = None
+    is_disabled: Optional[bool] = None
+    income_amount: Optional[Decimal] = None
+    valid_from: Optional[date] = None
+    valid_to: Optional[date] = None
+
+
+class Dependent(DependentBase):
+    """扶養家族の情報"""
+    dependent_id: int
+    employee_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class EmployeeBase(BaseModel):
+    """従業員の基本情報"""
+    employee_code: str
+    name: str
+    name_kana: Optional[str] = None
+    birth_date: Optional[date] = None
+    gender: Optional[str] = None
+    email: Optional[EmailStr] = None
+    phone: Optional[str] = None
+    postal_code: Optional[str] = None
+    address: Optional[str] = None
+    hire_date: date
+    termination_date: Optional[date] = None
+    is_active: bool = True
+    bank_name: Optional[str] = None
+    bank_branch: Optional[str] = None
+    bank_account_number: Optional[str] = None
+    bank_account_type: Optional[str] = None  # 普通/当座
+    notes: Optional[str] = None
+
+
+class EmployeeCreate(EmployeeBase):
+    """従業員の作成"""
+    pass
+
+
+class EmployeeUpdate(BaseModel):
+    """従業員の更新"""
+    employee_code: Optional[str] = None
+    name: Optional[str] = None
+    name_kana: Optional[str] = None
+    birth_date: Optional[date] = None
+    gender: Optional[str] = None
+    email: Optional[EmailStr] = None
+    phone: Optional[str] = None
+    postal_code: Optional[str] = None
+    address: Optional[str] = None
+    hire_date: Optional[date] = None
+    termination_date: Optional[date] = None
+    is_active: Optional[bool] = None
+    bank_name: Optional[str] = None
+    bank_branch: Optional[str] = None
+    bank_account_number: Optional[str] = None
+    bank_account_type: Optional[str] = None
+    notes: Optional[str] = None
+
+
+class Employee(EmployeeBase):
+    """従業員の情報"""
+    employee_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class EmployeeWithDependents(Employee):
+    """扶養家族を含む従業員情報"""
+    dependents: list[Dependent] = []
diff --git a/backend/app/payroll/settings/__init__.py b/backend/app/payroll/settings/__init__.py
new file mode 100644
index 0000000..0bee403
--- /dev/null
+++ b/backend/app/payroll/settings/__init__.py
@@ -0,0 +1,3 @@
+"""
+給与設定・税率・保険料管理 (Settings Management)
+"""
diff --git a/backend/app/payroll/settings/router.py b/backend/app/payroll/settings/router.py
new file mode 100644
index 0000000..bbc8b82
--- /dev/null
+++ b/backend/app/payroll/settings/router.py
@@ -0,0 +1,869 @@
+"""
+給与設定・税率・保険料管理API (Settings Management API)
+"""
+from fastapi import APIRouter, HTTPException, status, UploadFile, File
+from typing import List
+from datetime import date
+import csv
+import io
+from decimal import Decimal
+from pathlib import Path
+import openpyxl
+import xlrd
+from . import schemas
+from ...core.database import get_connection
+
+
+router = APIRouter(prefix="/payroll/settings", tags=["Payroll - Settings"])
+
+
+# ========================================
+# 給与基本設定
+# ========================================
+
+@router.post("/salary", response_model=schemas.SalarySetting, status_code=status.HTTP_201_CREATED)
+def create_salary_setting(setting: schemas.SalarySettingCreate):
+    """給与設定を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # 従業員の存在確認
+            cur.execute("SELECT employee_id FROM employees WHERE employee_id = %s", (setting.employee_id,))
+            if not cur.fetchone():
+                raise HTTPException(status_code=404, detail="従業員が見つかりません")
+            
+            cur.execute(
+                """
+                INSERT INTO salary_settings (
+                    employee_id, base_salary, hourly_rate, employment_type,
+                    payment_type, commute_allowance, other_allowance,
+                    valid_from, valid_to
+                ) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (
+                    setting.employee_id, setting.base_salary, setting.hourly_rate,
+                    setting.employment_type, setting.payment_type,
+                    setting.commute_allowance, setting.other_allowance,
+                    setting.valid_from, setting.valid_to
+                ),
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/salary/{employee_id}", response_model=List[schemas.SalarySetting])
+def get_salary_settings(employee_id: int):
+    """従業員の給与設定履歴を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM salary_settings 
+                WHERE employee_id = %s 
+                ORDER BY valid_from DESC
+                """,
+                (employee_id,)
+            )
+            return cur.fetchall()
+
+
+@router.get("/salary/{employee_id}/current", response_model=schemas.SalarySetting)
+def get_current_salary_setting(employee_id: int, target_date: date = None):
+    """従業員の現在の給与設定を取得"""
+    if target_date is None:
+        target_date = date.today()
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM salary_settings 
+                WHERE employee_id = %s 
+                AND valid_from <= %s
+                AND (valid_to IS NULL OR valid_to >= %s)
+                ORDER BY valid_from DESC
+                LIMIT 1
+                """,
+                (employee_id, target_date, target_date)
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="給与設定が見つかりません")
+            return result
+
+
+@router.put("/salary/{setting_id}", response_model=schemas.SalarySetting)
+def update_salary_setting(setting_id: int, setting: schemas.SalarySettingUpdate):
+    """給与設定を更新"""
+    update_data = setting.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [setting_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE salary_settings SET {set_clause} WHERE setting_id = %s RETURNING *",
+                values,
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="給与設定が見つかりません")
+            conn.commit()
+            return result
+
+
+# ========================================
+# 社会保険料率管理
+# ========================================
+
+@router.post("/insurance-rates", response_model=schemas.InsuranceRate, status_code=status.HTTP_201_CREATED)
+def create_insurance_rate(rate: schemas.InsuranceRateCreate):
+    """保険料率を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO insurance_rates (
+                    rate_year, rate_type, calculation_target, prefecture,
+                    employee_rate, employer_rate, care_insurance_age_threshold, notes
+                ) VALUES (%s, %s, %s, %s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (
+                    rate.rate_year, rate.rate_type, rate.calculation_target, rate.prefecture,
+                    rate.employee_rate, rate.employer_rate, rate.care_insurance_age_threshold, rate.notes
+                ),
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/insurance-rates", response_model=List[schemas.InsuranceRate])
+def get_insurance_rates(
+    rate_year: int = None, 
+    calculation_target: str = None, 
+    prefecture: str = None
+):
+    """保険料率一覧を取得（年度・計算対象・都道府県でフィルター可能）"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            conditions = []
+            params = []
+            
+            if rate_year:
+                conditions.append("rate_year = %s")
+                params.append(rate_year)
+            if calculation_target:
+                conditions.append("calculation_target = %s")
+                params.append(calculation_target)
+            if prefecture:
+                conditions.append("prefecture = %s")
+                params.append(prefecture)
+            
+            where_clause = " AND ".join(conditions) if conditions else "1=1"
+            
+            cur.execute(
+                f"""
+                SELECT * FROM insurance_rates 
+                WHERE {where_clause}
+                ORDER BY rate_year DESC, calculation_target, rate_type
+                """,
+                params
+            )
+            return cur.fetchall()
+
+
+@router.delete("/insurance-rates/{rate_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_insurance_rate(rate_id: int):
+    """保険料率を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM insurance_rates WHERE rate_id = %s RETURNING rate_id", (rate_id,))
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="保険料率が見つかりません")
+            conn.commit()
+
+
+@router.put("/insurance-rates/{rate_id}", response_model=schemas.InsuranceRate)
+def update_insurance_rate(rate_id: int, rate: schemas.InsuranceRateUpdate):
+    """保険料率を更新"""
+    print(f"\n=== 保険料率更新リクエスト ===")
+    print(f"Rate ID: {rate_id}")
+    print(f"受信データ: {rate}")
+    
+    update_data = rate.model_dump(exclude_unset=True)
+    print(f"更新データ: {update_data}")
+    
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [rate_id]
+    
+    print(f"SQL SET句: {set_clause}")
+    print(f"SQL値: {values}")
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            sql = f"UPDATE insurance_rates SET {set_clause} WHERE rate_id = %s RETURNING *"
+            print(f"実行SQL: {sql}")
+            
+            cur.execute(sql, values)
+            result = cur.fetchone()
+            
+            if not result:
+                raise HTTPException(status_code=404, detail="保険料率が見つかりません")
+            
+            print(f"更新結果: {result}")
+            conn.commit()
+            print("コミット完了")
+            return result
+
+
+# ========================================
+# 所得税率表管理
+# ========================================
+
+@router.post("/income-tax", response_model=schemas.IncomeTaxTable, status_code=status.HTTP_201_CREATED)
+def create_income_tax_table(tax: schemas.IncomeTaxTableCreate):
+    """所得税率表を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO income_tax_table (
+                    monthly_income_from, monthly_income_to, dependents_count,
+                    tax_amount, valid_from, valid_to
+                ) VALUES (%s, %s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (
+                    tax.monthly_income_from, tax.monthly_income_to,
+                    tax.dependents_count, tax.tax_amount,
+                    tax.valid_from, tax.valid_to
+                ),
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.post("/income-tax/import")
+def import_income_tax_table(file: UploadFile = File(...), tax_year: int = None):
+    """
+    所得税率表をCSV/Excelからインポート
+    税年度が指定されない場合、Excelファイルのタイトルから自動抽出（例：令和5年分 → 2023）
+    同じ年度の既存データは自動的に削除されます
+    """
+    imported_count = 0
+    filename = file.filename.lower()
+    extracted_year = tax_year
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            # Excel file処理
+            if filename.endswith(('.xlsx', '.xls')):
+                content = file.file.read()
+                
+                # .xls (旧形式) と .xlsx (新形式) で処理を分岐
+                if filename.endswith('.xls') and not filename.endswith('.xlsx'):
+                    # .xls形式 - xlrdを使用
+                    workbook = xlrd.open_workbook(file_contents=content)
+                    sheet = workbook.sheet_by_index(0)
+                    
+                    # 年度を自動抽出（まずB1セルを優先的にチェック）
+                    if not extracted_year:
+                        import re
+                        # B1セル(0行1列)を最優先でチェック
+                        if sheet.nrows > 0 and sheet.ncols > 1:
+                            b1_value = sheet.cell_value(0, 1)
+                            if b1_value and isinstance(b1_value, str):
+                                print(f"B1セルの値: {b1_value}")
+                                if '令和' in b1_value and '年' in b1_value:
+                                    match = re.search(r'令和(\d+)年', b1_value)
+                                    if match:
+                                        reiwa_year = int(match.group(1))
+                                        extracted_year = 2018 + reiwa_year
+                                        print(f"B1セルから年度を抽出: 令和{reiwa_year}年 = {extracted_year}")
+                                elif '平成' in b1_value and '年' in b1_value:
+                                    match = re.search(r'平成(\d+)年', b1_value)
+                                    if match:
+                                        heisei_year = int(match.group(1))
+                                        extracted_year = 1988 + heisei_year
+                                        print(f"B1セルから年度を抽出: 平成{heisei_year}年 = {extracted_year}")
+                        
+                        # B1から取得できない場合は他のセルも検索
+                        if not extracted_year:
+                            for row_idx in range(min(5, sheet.nrows)):
+                                for col_idx in range(sheet.ncols):
+                                    cell_value = sheet.cell_value(row_idx, col_idx)
+                                    if cell_value and isinstance(cell_value, str):
+                                        if '令和' in cell_value and '年' in cell_value:
+                                            match = re.search(r'令和(\d+)年', cell_value)
+                                            if match:
+                                                reiwa_year = int(match.group(1))
+                                                extracted_year = 2018 + reiwa_year
+                                                print(f"Excelから年度を抽出: 令和{reiwa_year}年 = {extracted_year}")
+                                                break
+                                        elif '平成' in cell_value and '年' in cell_value:
+                                            match = re.search(r'平成(\d+)年', cell_value)
+                                            if match:
+                                                heisei_year = int(match.group(1))
+                                                extracted_year = 1988 + heisei_year
+                                                print(f"Excelから年度を抽出: 平成{heisei_year}年 = {extracted_year}")
+                                                break
+                                if extracted_year:
+                                    break
+                    
+                    # 年度が取得できない場合は現在年度を使用
+                    if not extracted_year:
+                        extracted_year = date.today().year
+                        print(f"年度を自動設定: {extracted_year}")
+                    
+                    # 既存の同年度データを削除
+                    cur.execute("DELETE FROM income_tax_table WHERE tax_year = %s", (extracted_year,))
+                    deleted_count = cur.rowcount
+                    print(f"{extracted_year}年度の既存データを削除: {deleted_count}件")
+                    
+                    valid_from = date(extracted_year, 1, 1)
+                    valid_to = date(extracted_year, 12, 31)
+                    
+                    # ヘッダー行を探す（複数パターンに対応）
+                    header_row = None
+                    for row_idx in range(min(10, sheet.nrows)):
+                        for col_idx in range(sheet.ncols):
+                            cell_value = sheet.cell_value(row_idx, col_idx)
+                            if cell_value and (
+                                '社会保険料控除後' in str(cell_value) or
+                                '社会保' in str(cell_value) or
+                                '給与等の金額' in str(cell_value)
+                            ):
+                                header_row = row_idx
+                                print(f"ヘッダー行を検出: 行{row_idx}, セル値: {cell_value}")
+                                break
+                        if header_row is not None:
+                            break
+                    
+                    if header_row is None:
+                        # デバッグ用：最初の10行を出力
+                        print("デバッグ: 最初の10行を確認")
+                        for row_idx in range(min(10, sheet.nrows)):
+                            row_values = [str(sheet.cell_value(row_idx, c)) for c in range(min(5, sheet.ncols))]
+                            print(f"  行{row_idx}: {row_values}")
+                        raise HTTPException(status_code=400, detail="Excelのヘッダー行が見つかりません")
+                    
+                    # 扶養人数の列を特定
+                    dependents_cols = []
+                    header_row_idx = header_row + 2
+                    if header_row_idx < sheet.nrows:
+                        for col_idx in range(sheet.ncols):
+                            cell_value = sheet.cell_value(header_row_idx, col_idx)
+                            if cell_value and '人' in str(cell_value):
+                                try:
+                                    dep_count = int(str(cell_value).replace('人', '').strip())
+                                    dependents_cols.append((col_idx, dep_count))
+                                    print(f"扶養人数列を検出: 列{col_idx} = {dep_count}人")
+                                except Exception as e:
+                                    print(f"扶養人数解析エラー: {cell_value}, エラー: {e}")
+                                except:
+                                    pass
+                    
+                    # データ行を読み込む
+                    data_start_row = header_row + 3
+                    for row_idx in range(data_start_row, sheet.nrows):
+                        first_cell = sheet.cell_value(row_idx, 0)
+                        if not first_cell:
+                            continue
+                        
+                        try:
+                            income_from = None
+                            income_to = None
+                            
+                            for col_idx in range(min(3, sheet.ncols)):
+                                cell_value = sheet.cell_value(row_idx, col_idx)
+                                if cell_value:
+                                    val = str(cell_value).replace(',', '').replace('円', '').strip()
+                                    try:
+                                        if income_from is None:
+                                            income_from = Decimal(val)
+                                        elif income_to is None:
+                                            income_to = Decimal(val)
+                                            break
+                                    except:
+                                        pass
+                            
+                            if income_from is None:
+                                continue
+                            
+                            # 扶養人数ごとの税額を取得
+                            for col_idx, dep_count in dependents_cols:
+                                if col_idx < sheet.ncols:
+                                    tax_value = sheet.cell_value(row_idx, col_idx)
+                                    if tax_value not in (None, ''):
+                                        try:
+                                            tax_amount = Decimal(str(tax_value).replace(',', '').replace('円', '').strip())
+                                            cur.execute(
+                                                """
+                                                INSERT INTO income_tax_table (
+                                                    monthly_income_from, monthly_income_to, dependents_count,
+                                                    tax_amount, tax_year, valid_from, valid_to
+                                                ) VALUES (%s, %s, %s, %s, %s, %s, %s)
+                                                """,
+                                                (income_from, income_to, dep_count, tax_amount, extracted_year, valid_from, valid_to)
+                                            )
+                                            imported_count += 1
+                                        except Exception as e:
+                                            print(f"税額変換エラー: {tax_value}, エラー: {e}")
+                        except Exception as e:
+                            print(f"行処理エラー: {e}")
+                            continue
+                    
+                    # .xlsファイルの処理完了
+                    conn.commit()
+                    print(f"インポート完了: {imported_count}件のデータをインポートしました")
+                    return {"message": f"{extracted_year}年度の所得税率表を{imported_count}件インポートしました"}
+                
+                else:
+                    # .xlsx形式 - openpyxlを使用
+                    wb = openpyxl.load_workbook(io.BytesIO(content))
+                    ws = wb.active
+                
+                    # 年度を自動抽出（まずB1セルを優先的にチェック）
+                    if not extracted_year:
+                        import re
+                        # B1セルを最優先でチェック
+                        b1_cell = ws['B1']
+                        if b1_cell.value:
+                            b1_value = str(b1_cell.value)
+                            print(f"B1セルの値: {b1_value}")
+                            if '令和' in b1_value and '年' in b1_value:
+                                match = re.search(r'令和(\d+)年', b1_value)
+                                if match:
+                                    reiwa_year = int(match.group(1))
+                                    extracted_year = 2018 + reiwa_year
+                                    print(f"B1セルから年度を抽出: 令和{reiwa_year}年 = {extracted_year}")
+                            elif '平成' in b1_value and '年' in b1_value:
+                                match = re.search(r'平成(\d+)年', b1_value)
+                                if match:
+                                    heisei_year = int(match.group(1))
+                                    extracted_year = 1988 + heisei_year
+                                    print(f"B1セルから年度を抽出: 平成{heisei_year}年 = {extracted_year}")
+                        
+                        # B1から取得できない場合は他のセルも検索
+                        if not extracted_year:
+                            for row in ws.iter_rows(min_row=1, max_row=5):
+                                for cell in row:
+                                    if cell.value:
+                                        cell_text = str(cell.value)
+                                        if '令和' in cell_text and '年' in cell_text:
+                                            match = re.search(r'令和(\d+)年', cell_text)
+                                            if match:
+                                                reiwa_year = int(match.group(1))
+                                                extracted_year = 2018 + reiwa_year
+                                                print(f"Excelから年度を抽出: 令和{reiwa_year}年 = {extracted_year}")
+                                                break
+                                        elif '平成' in cell_text and '年' in cell_text:
+                                            match = re.search(r'平成(\d+)年', cell_text)
+                                            if match:
+                                                heisei_year = int(match.group(1))
+                                                extracted_year = 1988 + heisei_year
+                                                print(f"Excelから年度を抽出: 平成{heisei_year}年 = {extracted_year}")
+                                                break
+                                if extracted_year:
+                                    break
+                    
+                    # 年度が取得できない場合は現在年度を使用
+                    if not extracted_year:
+                        extracted_year = date.today().year
+                        print(f"年度を自動設定: {extracted_year}")
+                    
+                    # 既存の同年度データを削除
+                    cur.execute("DELETE FROM income_tax_table WHERE tax_year = %s", (extracted_year,))
+                    deleted_count = cur.rowcount
+                    print(f"{extracted_year}年度の既存データを削除: {deleted_count}件")
+                    
+                    # valid_from と valid_to を設定
+                    valid_from = date(extracted_year, 1, 1)
+                    valid_to = date(extracted_year, 12, 31)
+                    
+                    # ヘッダー行を探す
+                    header_row = None
+                    for row_idx, row in enumerate(ws.iter_rows(min_row=1, max_row=10), start=1):
+                        for cell in row:
+                            if cell.value and '社会保険料控除後' in str(cell.value):
+                                header_row = row_idx
+                                break
+                        if header_row:
+                            break
+                    
+                    if not header_row:
+                        raise HTTPException(status_code=400, detail="Excelのヘッダー行が見つかりません")
+                    
+                    # 扶養人数の列を特定
+                    dependents_cols = []
+                    header_row_data = list(ws.iter_rows(min_row=header_row+2, max_row=header_row+2))[0]
+                    for col_idx, cell in enumerate(header_row_data, start=1):
+                        if cell.value and '人' in str(cell.value):
+                            try:
+                                dep_count = int(str(cell.value).replace('人', '').strip())
+                                dependents_cols.append((col_idx, dep_count))
+                            except:
+                                pass
+                    
+                    # データ行を読み込む
+                    data_start_row = header_row + 3
+                    for row in ws.iter_rows(min_row=data_start_row):
+                        if not row[0].value:
+                            continue
+                        
+                        try:
+                            income_from = None
+                            income_to = None
+                            
+                            for i in range(min(3, len(row))):
+                                if row[i].value:
+                                    val = str(row[i].value).replace(',', '').replace('円', '').strip()
+                                    try:
+                                        if income_from is None:
+                                            income_from = Decimal(val)
+                                        elif income_to is None:
+                                            income_to = Decimal(val)
+                                            break
+                                    except:
+                                        pass
+                            
+                            if income_from is None:
+                                continue
+                            
+                            # 扶養人数ごとの税額を取得
+                            for col_idx, dep_count in dependents_cols:
+                                tax_value = row[col_idx - 1].value if col_idx - 1 < len(row) else None
+                                if tax_value is not None:
+                                    try:
+                                        tax_amount = Decimal(str(tax_value).replace(',', '').replace('円', '').strip())
+                                        
+                                        cur.execute(
+                                            """
+                                            INSERT INTO income_tax_table (
+                                                monthly_income_from, monthly_income_to, dependents_count,
+                                                tax_amount, tax_year, valid_from, valid_to
+                                            ) VALUES (%s, %s, %s, %s, %s, %s, %s)
+                                            """,
+                                            (income_from, income_to, dep_count, tax_amount, extracted_year, valid_from, valid_to)
+                                        )
+                                        imported_count += 1
+                                    except Exception as e:
+                                        print(f"税額変換エラー: {tax_value}, エラー: {e}")
+                                        pass
+                        except Exception as e:
+                            print(f"行処理エラー: {e}")
+                            continue
+                    
+                    # .xlsxファイルの処理完了
+                    conn.commit()
+                    print(f"インポート完了: {imported_count}件のデータをインポートしました")
+                    return {"message": f"{extracted_year}年度の所得税率表を{imported_count}件インポートしました"}
+            
+            # CSV file処理
+            else:
+                if not extracted_year:
+                    extracted_year = date.today().year
+                
+                # 既存の同年度データを削除
+                cur.execute("DELETE FROM income_tax_table WHERE tax_year = %s", (extracted_year,))
+                deleted_count = cur.rowcount
+                print(f"{extracted_year}年度の既存データを削除: {deleted_count}件")
+                
+                valid_from = date(extracted_year, 1, 1)
+                valid_to = date(extracted_year, 12, 31)
+                
+                content = file.file.read().decode("utf-8-sig")
+                csv_reader = csv.DictReader(io.StringIO(content))
+                
+                for row in csv_reader:
+                    cur.execute(
+                        """
+                        INSERT INTO income_tax_table (
+                            monthly_income_from, monthly_income_to, dependents_count,
+                            tax_amount, tax_year, valid_from, valid_to
+                        ) VALUES (%s, %s, %s, %s, %s, %s, %s)
+                        """,
+                        (
+                            Decimal(row["月収From"]),
+                            Decimal(row["月収To"]),
+                            int(row["扶養人数"]),
+                            Decimal(row["税額"]),
+                            extracted_year,
+                            valid_from,
+                            valid_to
+                        ),
+                    )
+                    imported_count += 1
+            
+            conn.commit()
+    
+    return {"message": f"{extracted_year}年度のデータを{imported_count}件インポートしました（既存データを置き換え）", "year": extracted_year}
+
+
+@router.get("/income-tax", response_model=List[schemas.IncomeTaxTable])
+def get_income_tax_table(target_date: date = None, dependents_count: int = None):
+    """所得税率表を取得"""
+    if target_date is None:
+        target_date = date.today()
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            if dependents_count is not None:
+                cur.execute(
+                    """
+                    SELECT * FROM income_tax_table 
+                    WHERE valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    AND dependents_count = %s
+                    ORDER BY monthly_income_from
+                    """,
+                    (target_date, target_date, dependents_count)
+                )
+            else:
+                cur.execute(
+                    """
+                    SELECT * FROM income_tax_table 
+                    WHERE valid_from <= %s
+                    AND (valid_to IS NULL OR valid_to >= %s)
+                    ORDER BY dependents_count, monthly_income_from
+                    """,
+                    (target_date, target_date)
+                )
+            return cur.fetchall()
+
+
+@router.get("/income-tax/calculate")
+def calculate_income_tax(monthly_income: Decimal, dependents_count: int = 0, target_date: date = None):
+    """月収と扶養人数から所得税額を計算"""
+    if target_date is None:
+        target_date = date.today()
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT tax_amount FROM income_tax_table 
+                WHERE valid_from <= %s
+                AND (valid_to IS NULL OR valid_to >= %s)
+                AND dependents_count = %s
+                AND monthly_income_from <= %s
+                AND monthly_income_to >= %s
+                LIMIT 1
+                """,
+                (target_date, target_date, dependents_count, monthly_income, monthly_income)
+            )
+            result = cur.fetchone()
+            
+            if not result:
+                return {"monthly_income": monthly_income, "dependents_count": dependents_count, "tax_amount": 0}
+            
+            return {
+                "monthly_income": monthly_income,
+                "dependents_count": dependents_count,
+                "tax_amount": result["tax_amount"]
+            }
+
+
+# ========================================
+# 社会保険料上限設定管理
+# ========================================
+
+@router.post("/insurance-limits", response_model=schemas.InsuranceLimitSetting, status_code=status.HTTP_201_CREATED)
+def create_insurance_limit(limit: schemas.InsuranceLimitSettingCreate):
+    """社会保険料上限設定を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO insurance_limit_settings (
+                    setting_type, limit_amount, valid_from, valid_to, notes
+                ) VALUES (%s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (limit.setting_type, limit.limit_amount, limit.valid_from, limit.valid_to, limit.notes)
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/insurance-limits", response_model=List[schemas.InsuranceLimitSetting])
+def get_insurance_limits(target_date: date = None):
+    """社会保険料上限設定一覧を取得"""
+    if target_date is None:
+        target_date = date.today()
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM insurance_limit_settings
+                WHERE valid_from <= %s
+                AND (valid_to IS NULL OR valid_to >= %s)
+                ORDER BY setting_type, valid_from DESC
+                """,
+                (target_date, target_date)
+            )
+            return cur.fetchall()
+
+
+@router.delete("/insurance-limits/{limit_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_insurance_limit(limit_id: int):
+    """社会保険料上限設定を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM insurance_limit_settings WHERE limit_id = %s RETURNING limit_id", (limit_id,))
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="上限設定が見つかりません")
+            conn.commit()
+
+
+@router.put("/insurance-limits/{limit_id}", response_model=schemas.InsuranceLimitSetting)
+def update_insurance_limit(limit_id: int, limit: schemas.InsuranceLimitSettingUpdate):
+    """社会保険料上限設定を更新"""
+    update_data = limit.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [limit_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE insurance_limit_settings SET {set_clause} WHERE limit_id = %s RETURNING *",
+                values
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="上限設定が見つかりません")
+            conn.commit()
+            return result
+
+
+# ========================================
+# 子ども・子育て拠出金率管理
+# ========================================
+
+@router.post("/child-support-rates", response_model=schemas.ChildSupportContributionRate, status_code=status.HTTP_201_CREATED)
+def create_child_support_rate(rate: schemas.ChildSupportContributionRateCreate):
+    """子ども・子育て拠出金率を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO child_support_contribution_rates (
+                    rate_year, income_threshold, contribution_rate, notes
+                ) VALUES (%s, %s, %s, %s)
+                RETURNING *
+                """,
+                (rate.rate_year, rate.income_threshold, rate.contribution_rate, rate.notes)
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/child-support-rates", response_model=List[schemas.ChildSupportContributionRate])
+def get_child_support_rates():
+    """子ども・子育て拠出金率一覧を取得"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM child_support_contribution_rates
+                ORDER BY rate_year DESC
+                """
+            )
+            return cur.fetchall()
+
+
+@router.delete("/child-support-rates/{contribution_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_child_support_rate(contribution_id: int):
+    """子ども・子育て拠出金率を削除"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute("DELETE FROM child_support_contribution_rates WHERE contribution_id = %s RETURNING contribution_id", (contribution_id,))
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="拠出金率が見つかりません")
+            conn.commit()
+
+
+@router.put("/child-support-rates/{contribution_id}", response_model=schemas.ChildSupportContributionRate)
+def update_child_support_rate(contribution_id: int, rate: schemas.ChildSupportContributionRateUpdate):
+    """子ども・子育て拠出金率を更新"""
+    update_data = rate.model_dump(exclude_unset=True)
+    if not update_data:
+        raise HTTPException(status_code=400, detail="更新するデータがありません")
+    
+    set_clause = ", ".join([f"{key} = %s" for key in update_data.keys()])
+    values = list(update_data.values()) + [contribution_id]
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                f"UPDATE child_support_contribution_rates SET {set_clause} WHERE contribution_id = %s RETURNING *",
+                values
+            )
+            result = cur.fetchone()
+            if not result:
+                raise HTTPException(status_code=404, detail="拠出金率が見つかりません")
+            conn.commit()
+            return result
+
+
+# ========================================
+# 扶養家族判定条件管理
+# ========================================
+
+@router.post("/dependent-rules", response_model=schemas.DependentRule, status_code=status.HTTP_201_CREATED)
+def create_dependent_rule(rule: schemas.DependentRuleCreate):
+    """扶養家族判定条件を作成"""
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                INSERT INTO dependent_rules (
+                    rule_type, rule_value, valid_from, valid_to, description
+                ) VALUES (%s, %s, %s, %s, %s)
+                RETURNING *
+                """,
+                (rule.rule_type, rule.rule_value, rule.valid_from, rule.valid_to, rule.description)
+            )
+            result = cur.fetchone()
+            conn.commit()
+            return result
+
+
+@router.get("/dependent-rules", response_model=List[schemas.DependentRule])
+def get_dependent_rules(target_date: date = None):
+    """扶養家族判定条件一覧を取得"""
+    if target_date is None:
+        target_date = date.today()
+    
+    with get_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT * FROM dependent_rules
+                WHERE valid_from <= %s
+                AND (valid_to IS NULL OR valid_to >= %s)
+                ORDER BY rule_type, valid_from DESC
+                """,
+                (target_date, target_date)
+            )
+            return cur.fetchall()
+
diff --git a/backend/app/payroll/settings/schemas.py b/backend/app/payroll/settings/schemas.py
new file mode 100644
index 0000000..d94a83c
--- /dev/null
+++ b/backend/app/payroll/settings/schemas.py
@@ -0,0 +1,220 @@
+"""
+給与設定・税率・保険料のスキーマ定義 (Settings Schemas)
+"""
+from pydantic import BaseModel
+from datetime import date, datetime
+from typing import Optional
+from decimal import Decimal
+
+
+class SalarySettingBase(BaseModel):
+    """給与基本設定"""
+    employee_id: int
+    base_salary: Decimal = Decimal("0")
+    hourly_rate: Optional[Decimal] = None
+    employment_type: str  # 正社員/契約社員/パート/アルバイト
+    payment_type: str  # 月給/時給/日給
+    commute_allowance: Decimal = Decimal("0")
+    other_allowance: Decimal = Decimal("0")
+    valid_from: date
+    valid_to: Optional[date] = None
+
+
+class SalarySettingCreate(SalarySettingBase):
+    """給与設定の作成"""
+    pass
+
+
+class SalarySettingUpdate(BaseModel):
+    """給与設定の更新"""
+    base_salary: Optional[Decimal] = None
+    hourly_rate: Optional[Decimal] = None
+    employment_type: Optional[str] = None
+    payment_type: Optional[str] = None
+    commute_allowance: Optional[Decimal] = None
+    other_allowance: Optional[Decimal] = None
+    valid_from: Optional[date] = None
+    valid_to: Optional[date] = None
+
+
+class SalarySetting(SalarySettingBase):
+    """給与設定の情報"""
+    setting_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class InsuranceRateBase(BaseModel):
+    """社会保険料率"""
+    rate_year: int  # 適用年度（例: 2026）
+    rate_type: str  # 健康保険/介護保険/厚生年金/雇用保険/労災保険
+    calculation_target: str  # 給与/賞与
+    prefecture: str = "東京都"  # 事業所所在地
+    employee_rate: Decimal
+    employer_rate: Decimal
+    care_insurance_age_threshold: Optional[int] = None  # 介護保険適用年齢下限
+    notes: Optional[str] = None
+
+
+class InsuranceRateCreate(InsuranceRateBase):
+    """保険料率の作成"""
+    pass
+
+
+class InsuranceRateUpdate(BaseModel):
+    """保険料率の更新"""
+    rate_year: Optional[int] = None
+    rate_type: Optional[str] = None
+    calculation_target: Optional[str] = None
+    prefecture: Optional[str] = None
+    employee_rate: Optional[Decimal] = None
+    employer_rate: Optional[Decimal] = None
+    care_insurance_age_threshold: Optional[int] = None
+    notes: Optional[str] = None
+
+
+class InsuranceRate(InsuranceRateBase):
+    """保険料率の情報"""
+    rate_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class IncomeTaxTableBase(BaseModel):
+    """所得税率表"""
+    monthly_income_from: Decimal
+    monthly_income_to: Decimal
+    dependents_count: int = 0
+    tax_amount: Decimal
+    valid_from: date
+    valid_to: Optional[date] = None
+
+
+class IncomeTaxTableCreate(IncomeTaxTableBase):
+    """所得税率表の作成"""
+    pass
+
+
+class IncomeTaxTable(IncomeTaxTableBase):
+    """所得税率表の情報"""
+    tax_id: int
+    created_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+# ========================================
+# 子ども・子育て拠出金率
+# ========================================
+
+class ChildSupportContributionRateBase(BaseModel):
+    """子ども・子育て拠出金率"""
+    rate_year: int  # 適用年度
+    income_threshold: Decimal  # 所得基準額（標準報酬月額）
+    contribution_rate: Decimal  # 拠出金率（事業主負担のみ）
+    notes: Optional[str] = None
+
+
+class ChildSupportContributionRateCreate(ChildSupportContributionRateBase):
+    """子ども・子育て拠出金率の作成"""
+    pass
+
+
+class ChildSupportContributionRateUpdate(BaseModel):
+    """子ども・子育て拠出金率の更新"""
+    income_threshold: Optional[Decimal] = None
+    contribution_rate: Optional[Decimal] = None
+    notes: Optional[str] = None
+
+
+class ChildSupportContributionRate(ChildSupportContributionRateBase):
+    """子ども・子育て拠出金率の情報"""
+    contribution_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+# ========================================
+# 社会保険料上限設定
+# ========================================
+
+class InsuranceLimitSettingBase(BaseModel):
+    """社会保険料上限設定"""
+    setting_type: str  # 健康保険標準報酬月額上限/厚生年金標準報酬月額上限/通勤手当非課税限度額
+    limit_amount: Decimal
+    valid_from: date
+    valid_to: Optional[date] = None
+    notes: Optional[str] = None
+
+
+class InsuranceLimitSettingCreate(InsuranceLimitSettingBase):
+    """上限設定の作成"""
+    pass
+
+
+class InsuranceLimitSettingUpdate(BaseModel):
+    """上限設定の更新"""
+    limit_amount: Optional[Decimal] = None
+    valid_from: Optional[date] = None
+    valid_to: Optional[date] = None
+    notes: Optional[str] = None
+
+
+class InsuranceLimitSetting(InsuranceLimitSettingBase):
+    """上限設定の情報"""
+    limit_id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+# ========================================
+# 扶養家族判定条件
+# ========================================
+
+class DependentRuleBase(BaseModel):
+    """扶養家族判定条件"""
+    rule_type: str  # 所得限度額/年齢条件/同一生計
+    rule_value: str
+    valid_from: date
+    valid_to: Optional[date] = None
+    description: Optional[str] = None
+
+
+class DependentRuleCreate(DependentRuleBase):
+    """判定条件の作成"""
+    pass
+
+
+class DependentRule(DependentRuleBase):
+    """判定条件の情報"""
+    rule_id: int
+    created_at: datetime
+
+    class Config:
+        from_attributes = True
+
+    """所得税率表の情報"""
+    tax_id: int
+    created_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class IncomeTaxImport(BaseModel):
+    """所得税率表のインポート用"""
+    data: list[IncomeTaxTableCreate]
+    valid_from: date
diff --git a/backend/app/static/payroll-calculation.html b/backend/app/static/payroll-calculation.html
new file mode 100644
index 0000000..4619a0f
--- /dev/null
+++ b/backend/app/static/payroll-calculation.html
@@ -0,0 +1,434 @@
+<!DOCTYPE html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>給与管理 - 月次給与計算</title>
+    <link rel="stylesheet" href="/css/style.css">
+    <style>
+        .filters {
+            margin-bottom: 20px;
+            padding: 15px;
+            background: #f9f9f9;
+            border-radius: 5px;
+        }
+        .filters label {
+            margin-right: 15px;
+        }
+        .payroll-list {
+            margin-top: 20px;
+        }
+        .payroll-item {
+            padding: 15px;
+            border: 1px solid #ddd;
+            margin-bottom: 10px;
+            border-radius: 5px;
+            cursor: pointer;
+        }
+        .payroll-item:hover {
+            background: #f9f9f9;
+        }
+        .status-badge {
+            padding: 4px 8px;
+            border-radius: 3px;
+            font-size: 12px;
+            font-weight: bold;
+        }
+        .status-draft {
+            background: #ffc107;
+            color: #000;
+        }
+        .status-calculated {
+            background: #17a2b8;
+            color: #fff;
+        }
+        .status-approved {
+            background: #28a745;
+            color: #fff;
+        }
+        .form-group {
+            margin-bottom: 15px;
+        }
+        .form-group label {
+            display: block;
+            margin-bottom: 5px;
+            font-weight: bold;
+        }
+        .form-group input, .form-group select {
+            width: 100%;
+            padding: 8px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+        }
+        .form-row {
+            display: grid;
+            grid-template-columns: repeat(3, 1fr);
+            gap: 15px;
+        }
+        .btn {
+            padding: 10px 20px;
+            margin-right: 10px;
+            border: none;
+            border-radius: 4px;
+            cursor: pointer;
+        }
+        .btn-primary {
+            background: #007bff;
+            color: white;
+        }
+        .btn-success {
+            background: #28a745;
+            color: white;
+        }
+        .btn-secondary {
+            background: #6c757d;
+            color: white;
+        }
+        .payroll-detail {
+            margin-top: 20px;
+        }
+        .detail-section {
+            margin-bottom: 20px;
+            padding: 15px;
+            background: #f9f9f9;
+            border-radius: 5px;
+        }
+        .detail-row {
+            display: flex;
+            justify-content: space-between;
+            padding: 8px 0;
+            border-bottom: 1px solid #ddd;
+        }
+        .detail-row:last-child {
+            border-bottom: none;
+        }
+        .total-row {
+            font-weight: bold;
+            font-size: 1.2em;
+            color: #007bff;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>給与管理 - 月次給与計算</h1>
+
+        <div class="filters">
+            <label>
+                対象年月:
+                <input type="number" id="filterYear" style="width: 100px;" placeholder="年">
+            </label>
+            <label>
+                <input type="number" id="filterMonth" style="width: 80px;" min="1" max="12" placeholder="月">
+            </label>
+            <button class="btn btn-primary" onclick="loadPayrolls()">検索</button>
+            <button class="btn btn-success" onclick="showCalculateForm()">新規計算</button>
+        </div>
+
+        <div id="payrollList" class="payroll-list"></div>
+
+        <!-- 給与計算フォーム（モーダル風） -->
+        <div id="calculateModal" style="display:none; position:fixed; top:50px; left:50%; transform:translateX(-50%); width:800px; max-height:90vh; overflow-y:auto; background:white; padding:30px; border:2px solid #007bff; border-radius:10px; box-shadow:0 4px 8px rgba(0,0,0,0.2); z-index:1000;">
+            <h2>給与計算</h2>
+            <form id="calculateForm" onsubmit="calculatePayroll(event)">
+                <div class="form-group">
+                    <label>従業員 *</label>
+                    <select name="employee_id" id="employeeSelect" required>
+                        <option value="">選択してください</option>
+                    </select>
+                </div>
+                
+                <div class="form-row">
+                    <div class="form-group">
+                        <label>対象年 *</label>
+                        <input type="number" name="payroll_year" required>
+                    </div>
+                    <div class="form-group">
+                        <label>対象月 *</label>
+                        <input type="number" name="payroll_month" min="1" max="12" required>
+                    </div>
+                    <div class="form-group">
+                        <label>支給日 *</label>
+                        <input type="date" name="payment_date" required>
+                    </div>
+                </div>
+
+                <div class="detail-section">
+                    <h3>勤怠情報</h3>
+                    <div class="form-row">
+                        <div class="form-group">
+                            <label>出勤日数</label>
+                            <input type="number" name="working_days" step="0.5" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>勤務時間</label>
+                            <input type="number" name="working_hours" step="0.5" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>残業時間</label>
+                            <input type="number" name="overtime_hours" step="0.5" value="0">
+                        </div>
+                    </div>
+                    <div class="form-row">
+                        <div class="form-group">
+                            <label>休日出勤時間</label>
+                            <input type="number" name="holiday_hours" step="0.5" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>遅刻時間</label>
+                            <input type="number" name="late_hours" step="0.5" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>欠勤日数</label>
+                            <input type="number" name="absent_days" step="0.5" value="0">
+                        </div>
+                    </div>
+                </div>
+
+                <div class="detail-section">
+                    <h3>その他</h3>
+                    <div class="form-row">
+                        <div class="form-group">
+                            <label>その他手当</label>
+                            <input type="number" name="other_allowance" step="0.01" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>住民税</label>
+                            <input type="number" name="resident_tax" step="0.01" value="0">
+                        </div>
+                        <div class="form-group">
+                            <label>その他控除</label>
+                            <input type="number" name="other_deduction" step="0.01" value="0">
+                        </div>
+                    </div>
+                </div>
+
+                <button type="submit" class="btn btn-primary">計算実行</button>
+                <button type="button" class="btn btn-secondary" onclick="closeCalculateForm()">キャンセル</button>
+            </form>
+        </div>
+
+        <!-- 給与明細表示 -->
+        <div id="payrollDetail" class="payroll-detail" style="display:none;"></div>
+    </div>
+
+    <script>
+        const API_BASE = 'http://localhost:8000';
+
+        async function loadEmployees() {
+            const response = await fetch(`${API_BASE}/payroll/employees/?is_active=true`);
+            const employees = await response.json();
+            
+            const select = document.getElementById('employeeSelect');
+            select.innerHTML = '<option value="">選択してください</option>' +
+                employees.map(emp => `<option value="${emp.employee_id}">${emp.employee_code} - ${emp.name}</option>`).join('');
+        }
+
+        async function loadPayrolls() {
+            const year = document.getElementById('filterYear').value;
+            const month = document.getElementById('filterMonth').value;
+            
+            const params = new URLSearchParams();
+            if (year) params.append('payroll_year', year);
+            if (month) params.append('payroll_month', month);
+            
+            try {
+                const response = await fetch(`${API_BASE}/payroll/calculation/?${params}`);
+                const payrolls = await response.json();
+                
+                const html = payrolls.map(p => `
+                    <div class="payroll-item" onclick="viewPayroll(${p.payroll_id})">
+                        <div>
+                            <strong>${p.payroll_year}年${p.payroll_month}月</strong>
+                            <span class="status-badge status-${p.status}">${getStatusLabel(p.status)}</span>
+                        </div>
+                        <div>
+                            従業員ID: ${p.employee_id} | 支給日: ${p.payment_date}
+                        </div>
+                        <div>
+                            <strong>差引支給額: ¥${Number(p.net_payment).toLocaleString()}</strong>
+                            (総支給: ¥${Number(p.total_payment).toLocaleString()} - 控除: ¥${Number(p.total_deduction).toLocaleString()})
+                        </div>
+                    </div>
+                `).join('');
+                
+                document.getElementById('payrollList').innerHTML = html || '<p>給与データがありません</p>';
+            } catch (error) {
+                alert('給与一覧の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        function getStatusLabel(status) {
+            const labels = {
+                'draft': '下書き',
+                'calculated': '計算済み',
+                'approved': '承認済み',
+                'paid': '支払済み'
+            };
+            return labels[status] || status;
+        }
+
+        function showCalculateForm() {
+            document.getElementById('calculateModal').style.display = 'block';
+            loadEmployees();
+            
+            // デフォルト値設定
+            const now = new Date();
+            document.querySelector('[name="payroll_year"]').value = now.getFullYear();
+            document.querySelector('[name="payroll_month"]').value = now.getMonth() + 1;
+        }
+
+        function closeCalculateForm() {
+            document.getElementById('calculateModal').style.display = 'none';
+            document.getElementById('calculateForm').reset();
+        }
+
+        async function calculatePayroll(event) {
+            event.preventDefault();
+            const form = event.target;
+            const formData = new FormData(form);
+            const data = {};
+            
+            formData.forEach((value, key) => {
+                data[key] = isNaN(value) || value === '' ? value : Number(value);
+            });
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/calculation/calculate`, {
+                    method: 'POST',
+                    headers: {'Content-Type': 'application/json'},
+                    body: JSON.stringify(data)
+                });
+
+                if (response.ok) {
+                    const result = await response.json();
+                    alert('給与計算が完了しました');
+                    closeCalculateForm();
+                    viewPayroll(result.payroll_id);
+                } else {
+                    const error = await response.json();
+                    alert('計算に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('計算に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function viewPayroll(payrollId) {
+            try {
+                const response = await fetch(`${API_BASE}/payroll/calculation/${payrollId}`);
+                const payroll = await response.json();
+
+                const html = `
+                    <h2>${payroll.payroll_year}年${payroll.payroll_month}月 給与明細</h2>
+                    <p>従業員ID: ${payroll.employee_id} | 支給日: ${payroll.payment_date}</p>
+                    <p>ステータス: <span class="status-badge status-${payroll.status}">${getStatusLabel(payroll.status)}</span></p>
+
+                    <div class="detail-section">
+                        <h3>勤怠情報</h3>
+                        <div class="detail-row"><span>出勤日数:</span><span>${payroll.working_days}日</span></div>
+                        <div class="detail-row"><span>勤務時間:</span><span>${payroll.working_hours}時間</span></div>
+                        <div class="detail-row"><span>残業時間:</span><span>${payroll.overtime_hours}時間</span></div>
+                        <div class="detail-row"><span>休日出勤:</span><span>${payroll.holiday_hours}時間</span></div>
+                        <div class="detail-row"><span>欠勤日数:</span><span>${payroll.absent_days}日</span></div>
+                    </div>
+
+                    <div class="detail-section">
+                        <h3>支給項目</h3>
+                        <div class="detail-row"><span>基本給:</span><span>¥${Number(payroll.base_salary).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>残業手当:</span><span>¥${Number(payroll.overtime_pay).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>休日手当:</span><span>¥${Number(payroll.holiday_pay).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>通勤手当:</span><span>¥${Number(payroll.commute_allowance).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>その他手当:</span><span>¥${Number(payroll.other_allowance).toLocaleString()}</span></div>
+                        <div class="detail-row total-row"><span>総支給額:</span><span>¥${Number(payroll.total_payment).toLocaleString()}</span></div>
+                    </div>
+
+                    <div class="detail-section">
+                        <h3>控除項目</h3>
+                        <div class="detail-row"><span>健康保険:</span><span>¥${Number(payroll.health_insurance).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>厚生年金:</span><span>¥${Number(payroll.pension_insurance).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>雇用保険:</span><span>¥${Number(payroll.employment_insurance).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>所得税:</span><span>¥${Number(payroll.income_tax).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>住民税:</span><span>¥${Number(payroll.resident_tax).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>その他控除:</span><span>¥${Number(payroll.other_deduction).toLocaleString()}</span></div>
+                        <div class="detail-row total-row"><span>総控除額:</span><span>¥${Number(payroll.total_deduction).toLocaleString()}</span></div>
+                    </div>
+
+                    <div class="detail-section" style="background:#e7f3ff;">
+                        <div class="detail-row total-row" style="font-size:1.5em;">
+                            <span>差引支給額:</span>
+                            <span>¥${Number(payroll.net_payment).toLocaleString()}</span>
+                        </div>
+                    </div>
+
+                    ${payroll.status === 'calculated' ? `
+                        <button class="btn btn-success" onclick="approvePayroll(${payroll.payroll_id})">承認</button>
+                        <button class="btn btn-primary" onclick="recalculatePayroll(${payroll.payroll_id})">再計算</button>
+                    ` : ''}
+                    <button class="btn btn-secondary" onclick="document.getElementById('payrollDetail').style.display='none'">閉じる</button>
+                `;
+
+                document.getElementById('payrollDetail').innerHTML = html;
+                document.getElementById('payrollDetail').style.display = 'block';
+                document.getElementById('payrollDetail').scrollIntoView({ behavior: 'smooth' });
+            } catch (error) {
+                alert('給与明細の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function approvePayroll(payrollId) {
+            if (!confirm('この給与を承認しますか?')) return;
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/calculation/${payrollId}/approve`, {
+                    method: 'POST',
+                    headers: {'Content-Type': 'application/json'},
+                    body: JSON.stringify({ approved_by: 'admin' })
+                });
+
+                if (response.ok) {
+                    alert('承認しました');
+                    viewPayroll(payrollId);
+                    loadPayrolls();
+                } else {
+                    const error = await response.json();
+                    alert('承認に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('承認に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function recalculatePayroll(payrollId) {
+            if (!confirm('給与を再計算しますか?')) return;
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/calculation/${payrollId}/recalculate`, {
+                    method: 'POST'
+                });
+
+                if (response.ok) {
+                    alert('再計算が完了しました');
+                    viewPayroll(payrollId);
+                } else {
+                    const error = await response.json();
+                    alert('再計算に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('再計算に失敗しました');
+                console.error(error);
+            }
+        }
+
+        // 初期化
+        const now = new Date();
+        document.getElementById('filterYear').value = now.getFullYear();
+        document.getElementById('filterMonth').value = now.getMonth() + 1;
+        loadPayrolls();
+    </script>
+</body>
+</html>
diff --git a/backend/app/static/payroll-employees.html b/backend/app/static/payroll-employees.html
new file mode 100644
index 0000000..ae63b17
--- /dev/null
+++ b/backend/app/static/payroll-employees.html
@@ -0,0 +1,302 @@
+<!DOCTYPE html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>給与管理 - 従業員管理</title>
+    <link rel="stylesheet" href="/css/style.css">
+    <style>
+        .nav-tabs {
+            display: flex;
+            gap: 10px;
+            margin-bottom: 20px;
+            border-bottom: 2px solid #ddd;
+        }
+        .nav-tab {
+            padding: 10px 20px;
+            cursor: pointer;
+            border: none;
+            background: #f0f0f0;
+            border-radius: 5px 5px 0 0;
+        }
+        .nav-tab.active {
+            background: #007bff;
+            color: white;
+        }
+        .tab-content {
+            display: none;
+        }
+        .tab-content.active {
+            display: block;
+        }
+        .employee-list {
+            margin-top: 20px;
+        }
+        .employee-item {
+            padding: 15px;
+            border: 1px solid #ddd;
+            margin-bottom: 10px;
+            border-radius: 5px;
+            cursor: pointer;
+        }
+        .employee-item:hover {
+            background: #f9f9f9;
+        }
+        .form-group {
+            margin-bottom: 15px;
+        }
+        .form-group label {
+            display: block;
+            margin-bottom: 5px;
+            font-weight: bold;
+        }
+        .form-group input, .form-group select, .form-group textarea {
+            width: 100%;
+            padding: 8px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+        }
+        .btn {
+            padding: 10px 20px;
+            margin-right: 10px;
+            border: none;
+            border-radius: 4px;
+            cursor: pointer;
+        }
+        .btn-primary {
+            background: #007bff;
+            color: white;
+        }
+        .btn-secondary {
+            background: #6c757d;
+            color: white;
+        }
+        .btn-danger {
+            background: #dc3545;
+            color: white;
+        }
+        .dependent-list {
+            margin-top: 20px;
+            padding: 15px;
+            background: #f9f9f9;
+            border-radius: 5px;
+        }
+        .dependent-item {
+            padding: 10px;
+            border: 1px solid #ddd;
+            margin-bottom: 10px;
+            background: white;
+            border-radius: 4px;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>給与管理 - 従業員管理</h1>
+
+        <div class="nav-tabs">
+            <button class="nav-tab active" onclick="showTab('list')">従業員一覧</button>
+            <button class="nav-tab" onclick="showTab('create')">新規登録</button>
+            <button class="nav-tab" onclick="showTab('detail')" id="detailTab" style="display:none;">従業員詳細</button>
+        </div>
+
+        <!-- 従業員一覧タブ -->
+        <div id="tab-list" class="tab-content active">
+            <div class="filters">
+                <label>
+                    <input type="checkbox" id="filterActive" checked onchange="loadEmployees()">
+                    在職中のみ表示
+                </label>
+            </div>
+            <div id="employeeList" class="employee-list"></div>
+        </div>
+
+        <!-- 新規登録タブ -->
+        <div id="tab-create" class="tab-content">
+            <h2>従業員の新規登録</h2>
+            <form id="createForm" onsubmit="createEmployee(event)">
+                <div class="form-group">
+                    <label>従業員コード *</label>
+                    <input type="text" name="employee_code" required>
+                </div>
+                <div class="form-group">
+                    <label>氏名 *</label>
+                    <input type="text" name="name" required>
+                </div>
+                <div class="form-group">
+                    <label>フリガナ</label>
+                    <input type="text" name="name_kana">
+                </div>
+                <div class="form-group">
+                    <label>メールアドレス</label>
+                    <input type="email" name="email">
+                </div>
+                <div class="form-group">
+                    <label>電話番号</label>
+                    <input type="tel" name="phone">
+                </div>
+                <div class="form-group">
+                    <label>入社日 *</label>
+                    <input type="date" name="hire_date" required>
+                </div>
+                <div class="form-group">
+                    <label>銀行名</label>
+                    <input type="text" name="bank_name">
+                </div>
+                <div class="form-group">
+                    <label>支店名</label>
+                    <input type="text" name="bank_branch">
+                </div>
+                <div class="form-group">
+                    <label>口座番号</label>
+                    <input type="text" name="bank_account_number">
+                </div>
+                <div class="form-group">
+                    <label>口座種別</label>
+                    <select name="bank_account_type">
+                        <option value="">選択してください</option>
+                        <option value="普通">普通</option>
+                        <option value="当座">当座</option>
+                    </select>
+                </div>
+                <div class="form-group">
+                    <label>備考</label>
+                    <textarea name="notes" rows="3"></textarea>
+                </div>
+                <button type="submit" class="btn btn-primary">登録</button>
+                <button type="button" class="btn btn-secondary" onclick="showTab('list')">キャンセル</button>
+            </form>
+        </div>
+
+        <!-- 従業員詳細タブ -->
+        <div id="tab-detail" class="tab-content">
+            <div id="employeeDetail"></div>
+        </div>
+    </div>
+
+    <script>
+        const API_BASE = 'http://localhost:8000';
+        let currentEmployee = null;
+
+        function showTab(tabName) {
+            document.querySelectorAll('.nav-tab').forEach(tab => tab.classList.remove('active'));
+            document.querySelectorAll('.tab-content').forEach(content => content.classList.remove('active'));
+
+            if (tabName === 'list') {
+                document.querySelector('.nav-tab').classList.add('active');
+                document.getElementById('tab-list').classList.add('active');
+                loadEmployees();
+            } else if (tabName === 'create') {
+                document.querySelectorAll('.nav-tab')[1].classList.add('active');
+                document.getElementById('tab-create').classList.add('active');
+            } else if (tabName === 'detail') {
+                document.getElementById('detailTab').classList.add('active');
+                document.getElementById('tab-detail').classList.add('active');
+            }
+        }
+
+        async function loadEmployees() {
+            const isActive = document.getElementById('filterActive').checked;
+            const url = `${API_BASE}/payroll/employees/${isActive ? '?is_active=true' : ''}`;
+            
+            try {
+                const response = await fetch(url);
+                const employees = await response.json();
+                
+                const html = employees.map(emp => `
+                    <div class="employee-item" onclick="viewEmployee(${emp.employee_id})">
+                        <strong>${emp.employee_code}</strong> - ${emp.name}
+                        ${emp.name_kana ? `(${emp.name_kana})` : ''}
+                        <br>
+                        <small>入社日: ${emp.hire_date} ${emp.termination_date ? ` | 退職日: ${emp.termination_date}` : ''}</small>
+                    </div>
+                `).join('');
+                
+                document.getElementById('employeeList').innerHTML = html || '<p>従業員が登録されていません</p>';
+            } catch (error) {
+                alert('従業員一覧の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function createEmployee(event) {
+            event.preventDefault();
+            const form = event.target;
+            const formData = new FormData(form);
+            const data = Object.fromEntries(formData.entries());
+            
+            // 空の値を除外
+            Object.keys(data).forEach(key => {
+                if (data[key] === '') {
+                    delete data[key];
+                }
+            });
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/employees/`, {
+                    method: 'POST',
+                    headers: {'Content-Type': 'application/json'},
+                    body: JSON.stringify(data)
+                });
+
+                if (response.ok) {
+                    alert('従業員を登録しました');
+                    form.reset();
+                    showTab('list');
+                } else {
+                    const error = await response.json();
+                    alert('登録に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('登録に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function viewEmployee(employeeId) {
+            try {
+                const response = await fetch(`${API_BASE}/payroll/employees/${employeeId}`);
+                const employee = await response.json();
+                currentEmployee = employee;
+
+                const html = `
+                    <h2>${employee.name} (${employee.employee_code})</h2>
+                    <p><strong>フリガナ:</strong> ${employee.name_kana || '-'}</p>
+                    <p><strong>メール:</strong> ${employee.email || '-'}</p>
+                    <p><strong>電話:</strong> ${employee.phone || '-'}</p>
+                    <p><strong>入社日:</strong> ${employee.hire_date}</p>
+                    <p><strong>退職日:</strong> ${employee.termination_date || '-'}</p>
+                    <p><strong>銀行:</strong> ${employee.bank_name || '-'} ${employee.bank_branch || ''}</p>
+                    <p><strong>口座:</strong> ${employee.bank_account_type || ''} ${employee.bank_account_number || '-'}</p>
+                    <p><strong>備考:</strong> ${employee.notes || '-'}</p>
+
+                    <div class="dependent-list">
+                        <h3>扶養家族</h3>
+                        ${employee.dependents.map(dep => `
+                            <div class="dependent-item">
+                                <strong>${dep.name}</strong> (${dep.relationship})
+                                ${dep.birth_date ? ` - 生年月日: ${dep.birth_date}` : ''}
+                                ${dep.is_spouse ? ' <span style="color:blue;">[配偶者]</span>' : ''}
+                                ${dep.is_disabled ? ' <span style="color:red;">[障害者]</span>' : ''}
+                                <br><small>有効期間: ${dep.valid_from} ～ ${dep.valid_to || '現在'}</small>
+                            </div>
+                        `).join('') || '<p>扶養家族が登録されていません</p>'}
+                    </div>
+
+                    <button class="btn btn-secondary" onclick="showTab('list')">戻る</button>
+                `;
+
+                document.getElementById('employeeDetail').innerHTML = html;
+                document.getElementById('detailTab').style.display = 'block';
+                showTab('detail');
+            } catch (error) {
+                alert('従業員情報の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        // 初期化
+        loadEmployees();
+    </script>
+</body>
+</html>
diff --git a/backend/app/static/payroll-salary-settings.html b/backend/app/static/payroll-salary-settings.html
new file mode 100644
index 0000000..0f9d7de
--- /dev/null
+++ b/backend/app/static/payroll-salary-settings.html
@@ -0,0 +1,291 @@
+<!DOCTYPE html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>給与管理 - 給与設定</title>
+    <link rel="stylesheet" href="/css/style.css">
+    <style>
+        .employee-select {
+            margin-bottom: 20px;
+            padding: 15px;
+            background: #f9f9f9;
+            border-radius: 5px;
+        }
+        .form-group {
+            margin-bottom: 15px;
+        }
+        .form-group label {
+            display: block;
+            margin-bottom: 5px;
+            font-weight: bold;
+        }
+        .form-group input, .form-group select {
+            width: 100%;
+            padding: 8px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+        }
+        .btn {
+            padding: 10px 20px;
+            margin-right: 10px;
+            border: none;
+            border-radius: 4px;
+            cursor: pointer;
+        }
+        .btn-primary {
+            background: #007bff;
+            color: white;
+        }
+        .btn-secondary {
+            background: #6c757d;
+            color: white;
+        }
+        table {
+            width: 100%;
+            border-collapse: collapse;
+            margin-top: 20px;
+        }
+        table th, table td {
+            border: 1px solid #ddd;
+            padding: 10px;
+            text-align: left;
+        }
+        table th {
+            background: #f0f0f0;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>給与管理 - 給与設定</h1>
+
+        <div class="employee-select">
+            <label><strong>従業員を選択:</strong></label>
+            <select id="employeeSelect" onchange="loadSalarySettings()">
+                <option value="">従業員を選択してください</option>
+            </select>
+        </div>
+
+        <div id="settingsContent" style="display:none;">
+            <h2>給与設定履歴</h2>
+            <button class="btn btn-primary" onclick="showAddForm()">新規設定追加</button>
+            <div id="settingsList"></div>
+
+            <div id="addForm" style="display:none; margin-top:20px; padding:20px; border:2px solid #007bff; border-radius:5px;">
+                <h3>給与設定の追加</h3>
+                <form onsubmit="saveSalarySetting(event)">
+                    <div class="form-group">
+                        <label>基本給 (円) *</label>
+                        <input type="number" name="base_salary" step="0.01" required>
+                    </div>
+                    <div class="form-group">
+                        <label>時給 (円)</label>
+                        <input type="number" name="hourly_rate" step="0.01">
+                        <small>時給制の場合に入力してください</small>
+                    </div>
+                    <div class="form-group">
+                        <label>雇用形態 *</label>
+                        <select name="employment_type" required>
+                            <option value="">選択してください</option>
+                            <option value="正社員">正社員</option>
+                            <option value="契約社員">契約社員</option>
+                            <option value="パート">パート</option>
+                            <option value="アルバイト">アルバイト</option>
+                        </select>
+                    </div>
+                    <div class="form-group">
+                        <label>支給形態 *</label>
+                        <select name="payment_type" required>
+                            <option value="">選択してください</option>
+                            <option value="月給">月給</option>
+                            <option value="時給">時給</option>
+                            <option value="日給">日給</option>
+                        </select>
+                    </div>
+                    <div class="form-group">
+                        <label>通勤手当 (円)</label>
+                        <input type="number" name="commute_allowance" step="0.01" value="0">
+                    </div>
+                    <div class="form-group">
+                        <label>その他手当 (円)</label>
+                        <input type="number" name="other_allowance" step="0.01" value="0">
+                    </div>
+                    <div class="form-group">
+                        <label>適用開始日 *</label>
+                        <input type="date" name="valid_from" required>
+                    </div>
+                    <div class="form-group">
+                        <label>適用終了日</label>
+                        <input type="date" name="valid_to">
+                        <small>通常は空欄のままにしてください</small>
+                    </div>
+                    <button type="submit" class="btn btn-primary">保存</button>
+                    <button type="button" class="btn btn-secondary" onclick="hideAddForm()">キャンセル</button>
+                </form>
+            </div>
+
+            <div id="currentSetting" style="margin-top:30px; padding:20px; background:#e7f3ff; border-radius:5px;">
+                <h3>現在の給与設定</h3>
+                <div id="currentSettingContent"></div>
+            </div>
+        </div>
+    </div>
+
+    <script>
+        const API_BASE = 'http://localhost:8000';
+        let currentEmployeeId = null;
+
+        async function loadEmployees() {
+            try {
+                const response = await fetch(`${API_BASE}/payroll/employees/?is_active=true`);
+                const employees = await response.json();
+                
+                const select = document.getElementById('employeeSelect');
+                select.innerHTML = '<option value="">従業員を選択してください</option>' +
+                    employees.map(emp => `<option value="${emp.employee_id}">${emp.employee_code} - ${emp.name}</option>`).join('');
+            } catch (error) {
+                alert('従業員一覧の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function loadSalarySettings() {
+            const employeeId = document.getElementById('employeeSelect').value;
+            if (!employeeId) {
+                document.getElementById('settingsContent').style.display = 'none';
+                return;
+            }
+
+            currentEmployeeId = employeeId;
+            document.getElementById('settingsContent').style.display = 'block';
+
+            try {
+                // 給与設定履歴を取得
+                const response = await fetch(`${API_BASE}/payroll/settings/salary/${employeeId}`);
+                const settings = await response.json();
+
+                const html = `
+                    <table>
+                        <thead>
+                            <tr>
+                                <th>適用期間</th>
+                                <th>基本給</th>
+                                <th>時給</th>
+                                <th>雇用形態</th>
+                                <th>支給形態</th>
+                                <th>通勤手当</th>
+                                <th>その他手当</th>
+                            </tr>
+                        </thead>
+                        <tbody>
+                            ${settings.map(s => `
+                                <tr>
+                                    <td>${s.valid_from} ～ ${s.valid_to || '現在'}</td>
+                                    <td>¥${Number(s.base_salary).toLocaleString()}</td>
+                                    <td>${s.hourly_rate ? '¥' + Number(s.hourly_rate).toLocaleString() : '-'}</td>
+                                    <td>${s.employment_type}</td>
+                                    <td>${s.payment_type}</td>
+                                    <td>¥${Number(s.commute_allowance).toLocaleString()}</td>
+                                    <td>¥${Number(s.other_allowance).toLocaleString()}</td>
+                                </tr>
+                            `).join('')}
+                        </tbody>
+                    </table>
+                `;
+
+                document.getElementById('settingsList').innerHTML = html;
+
+                // 現在の設定を取得
+                loadCurrentSetting(employeeId);
+            } catch (error) {
+                alert('給与設定の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function loadCurrentSetting(employeeId) {
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/salary/${employeeId}/current`);
+                if (response.ok) {
+                    const setting = await response.json();
+                    
+                    const html = `
+                        <div style="display:grid; grid-template-columns: repeat(2, 1fr); gap:15px;">
+                            <div><strong>基本給:</strong> ¥${Number(setting.base_salary).toLocaleString()}</div>
+                            <div><strong>時給:</strong> ${setting.hourly_rate ? '¥' + Number(setting.hourly_rate).toLocaleString() : '-'}</div>
+                            <div><strong>雇用形態:</strong> ${setting.employment_type}</div>
+                            <div><strong>支給形態:</strong> ${setting.payment_type}</div>
+                            <div><strong>通勤手当:</strong> ¥${Number(setting.commute_allowance).toLocaleString()}</div>
+                            <div><strong>その他手当:</strong> ¥${Number(setting.other_allowance).toLocaleString()}</div>
+                            <div><strong>適用期間:</strong> ${setting.valid_from} ～ ${setting.valid_to || '現在'}</div>
+                        </div>
+                    `;
+                    
+                    document.getElementById('currentSettingContent').innerHTML = html;
+                } else {
+                    document.getElementById('currentSettingContent').innerHTML = '<p>給与設定が登録されていません</p>';
+                }
+            } catch (error) {
+                document.getElementById('currentSettingContent').innerHTML = '<p>給与設定の取得に失敗しました</p>';
+            }
+        }
+
+        function showAddForm() {
+            document.getElementById('addForm').style.display = 'block';
+            // デフォルト値設定
+            document.querySelector('[name="valid_from"]').value = new Date().toISOString().split('T')[0];
+        }
+
+        function hideAddForm() {
+            document.getElementById('addForm').style.display = 'none';
+            document.querySelector('#addForm form').reset();
+        }
+
+        async function saveSalarySetting(event) {
+            event.preventDefault();
+            const form = event.target;
+            const formData = new FormData(form);
+            const data = Object.fromEntries(formData.entries());
+            
+            data.employee_id = parseInt(currentEmployeeId);
+            data.base_salary = parseFloat(data.base_salary) || 0;
+            data.commute_allowance = parseFloat(data.commute_allowance) || 0;
+            data.other_allowance = parseFloat(data.other_allowance) || 0;
+            
+            if (data.hourly_rate) {
+                data.hourly_rate = parseFloat(data.hourly_rate);
+            } else {
+                delete data.hourly_rate;
+            }
+            
+            if (!data.valid_to) {
+                delete data.valid_to;
+            }
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/salary`, {
+                    method: 'POST',
+                    headers: {'Content-Type': 'application/json'},
+                    body: JSON.stringify(data)
+                });
+
+                if (response.ok) {
+                    alert('給与設定を保存しました');
+                    hideAddForm();
+                    loadSalarySettings();
+                } else {
+                    const error = await response.json();
+                    alert('保存に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('保存に失敗しました');
+                console.error(error);
+            }
+        }
+
+        // 初期化
+        loadEmployees();
+    </script>
+</body>
+</html>
diff --git a/backend/app/static/payroll-settings.html b/backend/app/static/payroll-settings.html
new file mode 100644
index 0000000..3c4cc4f
--- /dev/null
+++ b/backend/app/static/payroll-settings.html
@@ -0,0 +1,326 @@
+<!DOCTYPE html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>給与管理 - 設定</title>
+    <link rel="stylesheet" href="/css/style.css">
+    <style>
+        .nav-tabs {
+            display: flex;
+            gap: 10px;
+            margin-bottom: 20px;
+            border-bottom: 2px solid #ddd;
+        }
+        .nav-tab {
+            padding: 10px 20px;
+            cursor: pointer;
+            border: none;
+            background: #f0f0f0;
+            border-radius: 5px 5px 0 0;
+        }
+        .nav-tab.active {
+            background: #007bff;
+            color: white;
+        }
+        .tab-content {
+            display: none;
+        }
+        .tab-content.active {
+            display: block;
+        }
+        .form-group {
+            margin-bottom: 15px;
+        }
+        .form-group label {
+            display: block;
+            margin-bottom: 5px;
+            font-weight: bold;
+        }
+        .form-group input, .form-group select {
+            width: 100%;
+            padding: 8px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+        }
+        .btn {
+            padding: 10px 20px;
+            margin-right: 10px;
+            border: none;
+            border-radius: 4px;
+            cursor: pointer;
+        }
+        .btn-primary {
+            background: #007bff;
+            color: white;
+        }
+        .btn-secondary {
+            background: #6c757d;
+            color: white;
+        }
+        table {
+            width: 100%;
+            border-collapse: collapse;
+            margin-top: 20px;
+        }
+        table th, table td {
+            border: 1px solid #ddd;
+            padding: 10px;
+            text-align: left;
+        }
+        table th {
+            background: #f0f0f0;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>給与管理 - 設定</h1>
+
+        <div class="nav-tabs">
+            <button class="nav-tab active" onclick="showTab('insurance')">保険料率</button>
+            <button class="nav-tab" onclick="showTab('tax')">所得税率表</button>
+        </div>
+
+        <!-- 保険料率タブ -->
+        <div id="tab-insurance" class="tab-content active">
+            <h2>社会保険料率設定</h2>
+            <button class="btn btn-primary" onclick="showInsuranceForm()">新規追加</button>
+            <div id="insuranceList"></div>
+
+            <div id="insuranceForm" style="display:none; margin-top:20px; padding:20px; border:2px solid #007bff; border-radius:5px;">
+                <h3>保険料率の登録</h3>
+                <form onsubmit="saveInsuranceRate(event)">
+                    <div class="form-group">
+                        <label>保険種類 *</label>
+                        <select name="rate_type" required>
+                            <option value="">選択してください</option>
+                            <option value="健康保険">健康保険</option>
+                            <option value="厚生年金">厚生年金</option>
+                            <option value="雇用保険">雇用保険</option>
+                            <option value="労災保険">労災保険</option>
+                        </select>
+                    </div>
+                    <div class="form-group">
+                        <label>従業員負担率 (%) *</label>
+                        <input type="number" name="employee_rate" step="0.0001" required placeholder="例: 5.0 (5%)">
+                    </div>
+                    <div class="form-group">
+                        <label>会社負担率 (%) *</label>
+                        <input type="number" name="employer_rate" step="0.0001" required placeholder="例: 5.0 (5%)">
+                    </div>
+                    <div class="form-group">
+                        <label>適用開始日 *</label>
+                        <input type="date" name="valid_from" required>
+                    </div>
+                    <div class="form-group">
+                        <label>適用終了日</label>
+                        <input type="date" name="valid_to">
+                    </div>
+                    <div class="form-group">
+                        <label>備考</label>
+                        <input type="text" name="notes">
+                    </div>
+                    <button type="submit" class="btn btn-primary">登録</button>
+                    <button type="button" class="btn btn-secondary" onclick="hideInsuranceForm()">キャンセル</button>
+                </form>
+            </div>
+        </div>
+
+        <!-- 所得税率表タブ -->
+        <div id="tab-tax" class="tab-content">
+            <h2>所得税率表</h2>
+            <div class="form-group" style="max-width:300px;">
+                <label>扶養人数でフィルター</label>
+                <select id="filterDependents" onchange="loadIncomeTax()">
+                    <option value="">全て</option>
+                    <option value="0">0人</option>
+                    <option value="1">1人</option>
+                    <option value="2">2人</option>
+                    <option value="3">3人</option>
+                    <option value="4">4人</option>
+                    <option value="5">5人以上</option>
+                </select>
+            </div>
+            <button class="btn btn-primary" onclick="document.getElementById('csvFile').click()">CSVインポート</button>
+            <input type="file" id="csvFile" accept=".csv" style="display:none;" onchange="importTaxTable(event)">
+            <div id="taxList"></div>
+        </div>
+    </div>
+
+    <script>
+        const API_BASE = 'http://localhost:8000';
+
+        function showTab(tabName) {
+            document.querySelectorAll('.nav-tab').forEach(tab => tab.classList.remove('active'));
+            document.querySelectorAll('.tab-content').forEach(content => content.classList.remove('active'));
+
+            if (tabName === 'insurance') {
+                document.querySelectorAll('.nav-tab')[0].classList.add('active');
+                document.getElementById('tab-insurance').classList.add('active');
+                loadInsuranceRates();
+            } else if (tabName === 'tax') {
+                document.querySelectorAll('.nav-tab')[1].classList.add('active');
+                document.getElementById('tab-tax').classList.add('active');
+                loadIncomeTax();
+            }
+        }
+
+        function showInsuranceForm() {
+            document.getElementById('insuranceForm').style.display = 'block';
+        }
+
+        function hideInsuranceForm() {
+            document.getElementById('insuranceForm').style.display = 'none';
+            document.querySelector('#insuranceForm form').reset();
+        }
+
+        async function loadInsuranceRates() {
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/insurance-rates`);
+                const rates = await response.json();
+
+                const html = `
+                    <table>
+                        <thead>
+                            <tr>
+                                <th>保険種類</th>
+                                <th>従業員負担率</th>
+                                <th>会社負担率</th>
+                                <th>適用期間</th>
+                                <th>備考</th>
+                            </tr>
+                        </thead>
+                        <tbody>
+                            ${rates.map(rate => `
+                                <tr>
+                                    <td>${rate.rate_type}</td>
+                                    <td>${(parseFloat(rate.employee_rate) * 100).toFixed(2)}%</td>
+                                    <td>${(parseFloat(rate.employer_rate) * 100).toFixed(2)}%</td>
+                                    <td>${rate.valid_from} ～ ${rate.valid_to || '現在'}</td>
+                                    <td>${rate.notes || '-'}</td>
+                                </tr>
+                            `).join('')}
+                        </tbody>
+                    </table>
+                `;
+
+                document.getElementById('insuranceList').innerHTML = html;
+            } catch (error) {
+                alert('保険料率の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function saveInsuranceRate(event) {
+            event.preventDefault();
+            const form = event.target;
+            const formData = new FormData(form);
+            const data = Object.fromEntries(formData.entries());
+
+            // パーセントを小数に変換
+            data.employee_rate = parseFloat(data.employee_rate) / 100;
+            data.employer_rate = parseFloat(data.employer_rate) / 100;
+
+            // 空の値を除外
+            if (!data.valid_to) delete data.valid_to;
+            if (!data.notes) delete data.notes;
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/insurance-rates`, {
+                    method: 'POST',
+                    headers: {'Content-Type': 'application/json'},
+                    body: JSON.stringify(data)
+                });
+
+                if (response.ok) {
+                    alert('保険料率を登録しました');
+                    hideInsuranceForm();
+                    loadInsuranceRates();
+                } else {
+                    const error = await response.json();
+                    alert('登録に失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('登録に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function loadIncomeTax() {
+            const dependentsFilter = document.getElementById('filterDependents').value;
+            const params = dependentsFilter ? `?dependents_count=${dependentsFilter}` : '';
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/income-tax${params}`);
+                const taxes = await response.json();
+
+                const html = `
+                    <table>
+                        <thead>
+                            <tr>
+                                <th>扶養人数</th>
+                                <th>月収From</th>
+                                <th>月収To</th>
+                                <th>税額</th>
+                                <th>適用期間</th>
+                            </tr>
+                        </thead>
+                        <tbody>
+                            ${taxes.map(tax => `
+                                <tr>
+                                    <td>${tax.dependents_count}人</td>
+                                    <td>¥${Number(tax.monthly_income_from).toLocaleString()}</td>
+                                    <td>¥${Number(tax.monthly_income_to).toLocaleString()}</td>
+                                    <td>¥${Number(tax.tax_amount).toLocaleString()}</td>
+                                    <td>${tax.valid_from} ～ ${tax.valid_to || '現在'}</td>
+                                </tr>
+                            `).join('')}
+                        </tbody>
+                    </table>
+                `;
+
+                document.getElementById('taxList').innerHTML = html;
+            } catch (error) {
+                alert('所得税率表の取得に失敗しました');
+                console.error(error);
+            }
+        }
+
+        async function importTaxTable(event) {
+            const file = event.target.files[0];
+            if (!file) return;
+
+            const formData = new FormData();
+            formData.append('file', file);
+
+            const validFrom = prompt('適用開始日を入力してください (YYYY-MM-DD):', new Date().toISOString().split('T')[0]);
+            if (!validFrom) return;
+
+            try {
+                const response = await fetch(`${API_BASE}/payroll/settings/income-tax/import?valid_from=${validFrom}`, {
+                    method: 'POST',
+                    body: formData
+                });
+
+                if (response.ok) {
+                    const result = await response.json();
+                    alert(result.message);
+                    loadIncomeTax();
+                } else {
+                    const error = await response.json();
+                    alert('インポートに失敗しました: ' + error.detail);
+                }
+            } catch (error) {
+                alert('インポートに失敗しました');
+                console.error(error);
+            }
+
+            event.target.value = '';
+        }
+
+        // 初期化
+        loadInsuranceRates();
+    </script>
+</body>
+</html>
diff --git a/backend/app/static/payroll.html b/backend/app/static/payroll.html
new file mode 100644
index 0000000..f09ae88
--- /dev/null
+++ b/backend/app/static/payroll.html
@@ -0,0 +1,99 @@
+<!DOCTYPE html>
+<html lang="ja">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>給与管理システム</title>
+    <link rel="stylesheet" href="/css/style.css">
+    <style>
+        .menu-grid {
+            display: grid;
+            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
+            gap: 20px;
+            margin-top: 30px;
+        }
+        .menu-card {
+            padding: 30px;
+            border: 2px solid #007bff;
+            border-radius: 10px;
+            text-align: center;
+            cursor: pointer;
+            transition: all 0.3s;
+        }
+        .menu-card:hover {
+            background: #007bff;
+            color: white;
+            transform: translateY(-5px);
+            box-shadow: 0 5px 15px rgba(0,123,255,0.3);
+        }
+        .menu-card h2 {
+            margin: 0 0 15px 0;
+            font-size: 1.5em;
+        }
+        .menu-card p {
+            margin: 0;
+            opacity: 0.8;
+        }
+        .menu-card:hover p {
+            opacity: 1;
+        }
+        .icon {
+            font-size: 3em;
+            margin-bottom: 15px;
+        }
+        .back-link {
+            display: inline-block;
+            margin-bottom: 20px;
+            color: #007bff;
+            text-decoration: none;
+        }
+        .back-link:hover {
+            text-decoration: underline;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <a href="../index.html" class="back-link">← メインメニューに戻る</a>
+        
+        <h1>給与管理システム</h1>
+        <p>従業員の給与計算、扶養管理、保険料・税金の管理を行います</p>
+
+        <div class="menu-grid">
+            <div class="menu-card" onclick="location.href='payroll-employees.html'">
+                <div class="icon">👥</div>
+                <h2>従業員管理</h2>
+                <p>従業員の基本情報、扶養家族情報を管理します</p>
+            </div>
+
+            <div class="menu-card" onclick="location.href='payroll-salary-settings.html'">
+                <div class="icon">💰</div>
+                <h2>給与設定</h2>
+                <p>各従業員の給与設定、基本給、手当などを管理します</p>
+            </div>
+
+            <div class="menu-card" onclick="location.href='payroll-calculation.html'">
+                <div class="icon">🧮</div>
+                <h2>月次給与計算</h2>
+                <p>毎月の給与計算、給与明細の作成・承認を行います</p>
+            </div>
+
+            <div class="menu-card" onclick="location.href='payroll-settings.html'">
+                <div class="icon">⚙️</div>
+                <h2>税率・保険料設定</h2>
+                <p>社会保険料率、所得税率表の管理を行います</p>
+            </div>
+        </div>
+
+        <div style="margin-top: 50px; padding: 20px; background: #f0f8ff; border-radius: 5px;">
+            <h3>📋 給与システムの使い方</h3>
+            <ol>
+                <li><strong>従業員管理</strong>で従業員を登録し、扶養家族情報を入力します</li>
+                <li><strong>給与設定</strong>で各従業員の基本給や手当を設定します</li>
+                <li><strong>税率・保険料設定</strong>で社会保険料率や所得税率表を確認・更新します</li>
+                <li><strong>月次給与計算</strong>で勤怠情報を入力し、給与を計算・承認します</li>
+            </ol>
+        </div>
+    </div>
+</body>
+</html>
diff --git a/backend/check_excel.py b/backend/check_excel.py
new file mode 100644
index 0000000..7f0af5b
--- /dev/null
+++ b/backend/check_excel.py
@@ -0,0 +1,20 @@
+import xlrd
+
+file_path = r"C:\workspace\njts-accounting-core\reports\tmp\01-07 (3).xls"
+workbook = xlrd.open_workbook(file_path)
+sheet = workbook.sheet_by_index(0)
+
+print(f"シート名: {sheet.name}")
+print(f"行数: {sheet.nrows}, 列数: {sheet.ncols}")
+print("\n最初の15行:")
+print("=" * 100)
+
+for row_idx in range(min(15, sheet.nrows)):
+    row_values = []
+    for col_idx in range(min(15, sheet.ncols)):
+        cell_value = sheet.cell_value(row_idx, col_idx)
+        if cell_value == '':
+            row_values.append('')
+        else:
+            row_values.append(str(cell_value))
+    print(f"行{row_idx}: {' | '.join(row_values)}")
diff --git a/backend/check_precision.py b/backend/check_precision.py
new file mode 100644
index 0000000..75ef7b3
--- /dev/null
+++ b/backend/check_precision.py
@@ -0,0 +1,59 @@
+import os
+import psycopg2
+from dotenv import load_dotenv
+
+# Load environment variables from root .env
+root_env = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.env')
+load_dotenv(root_env)
+
+# Connect to database
+conn = psycopg2.connect(
+    host=os.getenv('DB_HOST', '192.168.0.61'),
+    port=os.getenv('DB_PORT', '55432'),
+    dbname=os.getenv('DB_NAME', 'njts_acct'),
+    user=os.getenv('DB_USER', 'njts_app'),
+    password=os.getenv('DB_PASSWORD')
+)
+
+cur = conn.cursor()
+
+# Check current column precision
+cur.execute("""
+    SELECT column_name, data_type, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='insurance_rates' 
+    AND column_name IN ('employee_rate', 'employer_rate') 
+    ORDER BY column_name
+""")
+
+print("insurance_rates カラムの現在の精度:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: {row[1]}({row[2]},{row[3]})")
+
+# Check child_support_contribution_rates
+cur.execute("""
+    SELECT column_name, data_type, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='child_support_contribution_rates' 
+    AND column_name = 'contribution_rate'
+""")
+
+print("\nchild_support_contribution_rates カラムの現在の精度:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: {row[1]}({row[2]},{row[3]})")
+
+# Check actual data
+cur.execute("""
+    SELECT rate_year, rate_type, calculation_target, prefecture, 
+           employee_rate, employer_rate
+    FROM insurance_rates 
+    WHERE rate_year = 2025 AND rate_type = '健康保険'
+    LIMIT 3
+""")
+
+print("\n実際のデータ (2025年健康保険):")
+for row in cur.fetchall():
+    print(f"  {row[0]} {row[1]} {row[2]} {row[3]}: 従業員={row[4]} 会社={row[5]}")
+
+cur.close()
+conn.close()
diff --git a/backend/create_payroll_db.py b/backend/create_payroll_db.py
new file mode 100644
index 0000000..12ad93e
--- /dev/null
+++ b/backend/create_payroll_db.py
@@ -0,0 +1,72 @@
+"""
+給与システムデータベース初期化スクリプト
+Payroll Database Initialization Script
+"""
+import psycopg
+import os
+from dotenv import load_dotenv
+
+# 環境変数を読み込む
+load_dotenv()
+
+# データベース接続文字列を構築
+DB_HOST = os.getenv("DB_HOST", "192.168.0.61")
+DB_PORT = os.getenv("DB_PORT", "55432")
+DB_NAME = os.getenv("DB_NAME", "njts_acct")
+DB_USER = os.getenv("DB_USER", "njts_app")
+DB_PASSWORD = os.getenv("DB_PASSWORD", "njts_app2025")
+
+DATABASE_URL = f"postgresql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}:{DB_PORT}/{DB_NAME}"
+
+def create_payroll_database():
+    """SQLファイルを実行してデータベースを初期化"""
+    
+    # SQLファイルのパスを取得
+    import os
+    script_dir = os.path.dirname(os.path.abspath(__file__))
+    sql_file = os.path.join(script_dir, 'sql', 'payroll_schema_complete.sql')
+    
+    # SQLファイルを読み込む
+    with open(sql_file, 'r', encoding='utf-8') as f:
+        sql_script = f.read()
+    
+    try:
+        # データベースに接続
+        print(f"データベースに接続中: {DATABASE_URL}")
+        conn = psycopg.connect(DATABASE_URL)
+        
+        # トランザクションを開始
+        with conn:
+            with conn.cursor() as cur:
+                # SQLスクリプトを実行
+                print("SQLスクリプトを実行中...")
+                cur.execute(sql_script)
+                print("✅ データベースの初期化が完了しました！")
+                
+                # テーブル一覧を確認
+                cur.execute("""
+                    SELECT table_name 
+                    FROM information_schema.tables 
+                    WHERE table_schema = 'public' 
+                    ORDER BY table_name
+                """)
+                tables = cur.fetchall()
+                print("\n作成されたテーブル:")
+                for table in tables:
+                    print(f"  - {table[0]}")
+                
+                # 保険料率データを確認
+                cur.execute("SELECT COUNT(*) FROM insurance_rates")
+                count = cur.fetchone()[0]
+                print(f"\n保険料率データ: {count}件")
+                
+        conn.close()
+        print("\n✅ データベース初期化が正常に完了しました！")
+        
+    except Exception as e:
+        print(f"\n❌ エラーが発生しました: {e}")
+        print(f"\nエラーの詳細: {type(e).__name__}")
+        raise
+
+if __name__ == "__main__":
+    create_payroll_database()
diff --git a/backend/fix_precision.py b/backend/fix_precision.py
new file mode 100644
index 0000000..f6bab3d
--- /dev/null
+++ b/backend/fix_precision.py
@@ -0,0 +1,68 @@
+import os
+import psycopg2
+from dotenv import load_dotenv
+
+# Load environment variables
+root_env = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.env')
+load_dotenv(root_env)
+
+# Connect to database
+conn = psycopg2.connect(
+    host=os.getenv('DB_HOST', '192.168.0.61'),
+    port=os.getenv('DB_PORT', '55432'),
+    dbname=os.getenv('DB_NAME', 'njts_acct'),
+    user=os.getenv('DB_USER', 'njts_app'),
+    password=os.getenv('DB_PASSWORD')
+)
+
+cur = conn.cursor()
+
+print("保険率カラムを DECIMAL(7,5) に変更中...")
+print("これにより、4.955% (0.04955) のような値を正確に保存できます。")
+
+# Alter insurance_rates table to DECIMAL(7,5)
+cur.execute("""
+    ALTER TABLE insurance_rates 
+    ALTER COLUMN employee_rate TYPE DECIMAL(7, 5),
+    ALTER COLUMN employer_rate TYPE DECIMAL(7, 5)
+""")
+
+# Alter child_support_contribution_rates table
+cur.execute("""
+    ALTER TABLE child_support_contribution_rates 
+    ALTER COLUMN contribution_rate TYPE DECIMAL(7, 5)
+""")
+
+conn.commit()
+
+print("OK カラム変更完了")
+
+# Verify
+cur.execute("""
+    SELECT column_name, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='insurance_rates' 
+    AND column_name IN ('employee_rate', 'employer_rate') 
+    ORDER BY column_name
+""")
+
+print("\n変更後の insurance_rates カラム:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: numeric({row[1]},{row[2]})")
+
+cur.execute("""
+    SELECT column_name, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='child_support_contribution_rates' 
+    AND column_name = 'contribution_rate'
+""")
+
+print("\n変更後の child_support_contribution_rates カラム:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: numeric({row[1]},{row[2]})")
+
+cur.close()
+conn.close()
+
+print("\n完了！")
+print("これで 4.955% を入力すると、0.04955 として正確に保存され、4.955% と表示されます。")
diff --git a/backend/income_tax_sample.csv b/backend/income_tax_sample.csv
new file mode 100644
index 0000000..cd36884
--- /dev/null
+++ b/backend/income_tax_sample.csv
@@ -0,0 +1,51 @@
+月収From,月収To,扶養人数,税額
+0,88000,0,0
+88000,89000,0,130
+89000,90000,0,180
+90000,93000,0,230
+93000,95000,0,280
+95000,97000,0,380
+97000,99000,0,480
+99000,101000,0,580
+101000,103000,0,680
+103000,105000,0,780
+105000,107000,0,880
+107000,109000,0,1020
+109000,118000,0,1160
+118000,120000,0,1300
+120000,122000,0,1440
+122000,124000,0,1580
+124000,126000,0,1720
+126000,128000,0,1860
+128000,130000,0,2000
+130000,132000,0,2140
+132000,134000,0,2280
+134000,136000,0,2420
+136000,138000,0,2560
+138000,140000,0,2700
+140000,142000,0,2840
+142000,144000,0,2980
+144000,146000,0,3120
+146000,148000,0,3260
+148000,150000,0,3400
+0,96000,1,0
+96000,98000,1,130
+98000,100000,1,180
+100000,102000,1,230
+102000,104000,1,280
+104000,106000,1,380
+106000,108000,1,480
+108000,110000,1,580
+110000,112000,1,680
+112000,114000,1,780
+114000,116000,1,880
+116000,118000,1,1020
+118000,127000,1,1160
+127000,129000,1,1300
+129000,131000,1,1440
+131000,133000,1,1580
+133000,135000,1,1720
+135000,137000,1,1860
+137000,139000,1,2000
+139000,141000,1,2140
+141000,143000,1,2280
diff --git a/backend/requirements.txt b/backend/requirements.txt
index 1a34c78..54628d1 100644
Binary files a/backend/requirements.txt and b/backend/requirements.txt differ
diff --git a/backend/revert_precision.py b/backend/revert_precision.py
new file mode 100644
index 0000000..dea1c69
--- /dev/null
+++ b/backend/revert_precision.py
@@ -0,0 +1,56 @@
+import os
+import psycopg2
+from dotenv import load_dotenv
+
+# Load environment variables
+root_env = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.env')
+load_dotenv(root_env)
+
+# Connect to database
+conn = psycopg2.connect(
+    host=os.getenv('DB_HOST', '192.168.0.61'),
+    port=os.getenv('DB_PORT', '55432'),
+    dbname=os.getenv('DB_NAME', 'njts_acct'),
+    user=os.getenv('DB_USER', 'njts_app'),
+    password=os.getenv('DB_PASSWORD')
+)
+
+cur = conn.cursor()
+
+print("保険率カラムを DECIMAL(6,4) に戻しています...")
+
+# Alter insurance_rates table back to DECIMAL(6,4)
+cur.execute("""
+    ALTER TABLE insurance_rates 
+    ALTER COLUMN employee_rate TYPE DECIMAL(6, 4),
+    ALTER COLUMN employer_rate TYPE DECIMAL(6, 4)
+""")
+
+# Alter child_support_contribution_rates table
+cur.execute("""
+    ALTER TABLE child_support_contribution_rates 
+    ALTER COLUMN contribution_rate TYPE DECIMAL(6, 4)
+""")
+
+conn.commit()
+
+print("OK データベース変更完了")
+
+# Verify
+cur.execute("""
+    SELECT column_name, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='insurance_rates' 
+    AND column_name IN ('employee_rate', 'employer_rate') 
+    ORDER BY column_name
+""")
+
+print("\n変更後:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: numeric({row[1]},{row[2]})")
+
+cur.close()
+conn.close()
+
+print("\nデータベースは DECIMAL(6,4) で、フロントエンドの表示を小数点以下3桁にします。")
+print("これにより、4.955% のような値を正確に保存しつつ、表示は3桁に丸めることができます。")
diff --git a/backend/sql/add_tax_year.sql b/backend/sql/add_tax_year.sql
new file mode 100644
index 0000000..9b2454e
--- /dev/null
+++ b/backend/sql/add_tax_year.sql
@@ -0,0 +1,17 @@
+-- 所得税率表に年度フィールドを追加
+ALTER TABLE income_tax_table 
+ADD COLUMN tax_year INTEGER;
+
+-- 既存データに年度を設定（valid_fromから抽出）
+UPDATE income_tax_table 
+SET tax_year = EXTRACT(YEAR FROM valid_from);
+
+-- 年度をNOT NULLに変更
+ALTER TABLE income_tax_table 
+ALTER COLUMN tax_year SET NOT NULL;
+
+-- インデックスを追加
+CREATE INDEX idx_income_tax_year ON income_tax_table(tax_year);
+
+-- コメント
+COMMENT ON COLUMN income_tax_table.tax_year IS '適用年度';
diff --git a/backend/sql/payroll_enhancements.sql b/backend/sql/payroll_enhancements.sql
new file mode 100644
index 0000000..2132aba
--- /dev/null
+++ b/backend/sql/payroll_enhancements.sql
@@ -0,0 +1,116 @@
+-- 給与システム拡張機能
+-- Payroll System Enhancements
+
+-- ========================================
+-- 1. 社会保険料上限設定テーブル
+-- ========================================
+CREATE TABLE IF NOT EXISTS insurance_limit_settings (
+    limit_id SERIAL PRIMARY KEY,
+    setting_type VARCHAR(50) NOT NULL, -- 健康保険上限/厚生年金上限/通勤手当非課税限度額
+    limit_amount DECIMAL(12, 2) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE insurance_limit_settings IS '社会保険料上限設定';
+COMMENT ON COLUMN insurance_limit_settings.setting_type IS '設定種別: 健康保険上限/厚生年金上限/通勤手当非課税限度額';
+COMMENT ON COLUMN insurance_limit_settings.limit_amount IS '上限額';
+
+-- ========================================
+-- 2. 賞与計算テーブル
+-- ========================================
+CREATE TABLE IF NOT EXISTS bonus_payments (
+    bonus_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id),
+    bonus_year INTEGER NOT NULL,
+    bonus_month INTEGER NOT NULL,
+    bonus_type VARCHAR(50) NOT NULL, -- 夏季賞与/冬季賞与/決算賞与/その他
+    payment_date DATE NOT NULL,
+    status VARCHAR(20) DEFAULT 'draft', -- draft/calculated/approved/paid
+    
+    -- 支給項目
+    base_bonus DECIMAL(12, 2) DEFAULT 0, -- 基本賞与額
+    performance_bonus DECIMAL(12, 2) DEFAULT 0, -- 業績賞与
+    other_bonus DECIMAL(12, 2) DEFAULT 0, -- その他賞与
+    total_bonus DECIMAL(12, 2) DEFAULT 0, -- 総支給額
+    
+    -- 控除項目
+    health_insurance DECIMAL(12, 2) DEFAULT 0,
+    care_insurance DECIMAL(12, 2) DEFAULT 0, -- 介護保険（40歳以上）
+    pension_insurance DECIMAL(12, 2) DEFAULT 0,
+    employment_insurance DECIMAL(12, 2) DEFAULT 0,
+    income_tax DECIMAL(12, 2) DEFAULT 0, -- 賞与所得税
+    other_deduction DECIMAL(12, 2) DEFAULT 0,
+    total_deduction DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 差引支給額
+    net_bonus DECIMAL(12, 2) DEFAULT 0,
+    
+    notes TEXT,
+    calculated_at TIMESTAMP,
+    calculated_by VARCHAR(100),
+    approved_at TIMESTAMP,
+    approved_by VARCHAR(100),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    
+    CONSTRAINT uc_bonus_employee_payment UNIQUE (employee_id, bonus_year, bonus_month, bonus_type)
+);
+
+COMMENT ON TABLE bonus_payments IS '賞与計算';
+COMMENT ON COLUMN bonus_payments.bonus_type IS '賞与種別: 夏季賞与/冬季賞与/決算賞与/その他';
+COMMENT ON COLUMN bonus_payments.status IS 'ステータス: draft/calculated/approved/paid';
+
+-- ========================================
+-- 3. 扶養家族判定条件テーブル（所得税計算用）
+-- ========================================
+CREATE TABLE IF NOT EXISTS dependent_rules (
+    rule_id SERIAL PRIMARY KEY,
+    rule_type VARCHAR(50) NOT NULL, -- 所得限度額/年齢条件/同一生計
+    rule_value VARCHAR(100) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    description TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE dependent_rules IS '扶養家族判定条件';
+COMMENT ON COLUMN dependent_rules.rule_type IS 'ルール種別: 所得限度額/年齢条件/同一生計';
+
+-- ========================================
+-- インデックス作成
+-- ========================================
+CREATE INDEX idx_insurance_limits_valid ON insurance_limit_settings(valid_from, valid_to);
+CREATE INDEX idx_bonus_employee_year ON bonus_payments(employee_id, bonus_year);
+CREATE INDEX idx_bonus_status ON bonus_payments(status);
+CREATE INDEX idx_dependent_rules_valid ON dependent_rules(valid_from, valid_to);
+
+-- ========================================
+-- トリガー: 更新日時の自動更新
+-- ========================================
+CREATE TRIGGER trg_insurance_limits_updated_at BEFORE UPDATE ON insurance_limit_settings
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_bonus_payments_updated_at BEFORE UPDATE ON bonus_payments
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+-- ========================================
+-- 初期データ: 社会保険料上限設定 (2026年度)
+-- ========================================
+INSERT INTO insurance_limit_settings (setting_type, limit_amount, valid_from, notes) VALUES
+('健康保険標準報酬月額上限', 1390000, '2026-01-01', '健康保険の標準報酬月額上限（第50級）'),
+('厚生年金標準報酬月額上限', 650000, '2026-01-01', '厚生年金保険の標準報酬月額上限（第32級）'),
+('通勤手当非課税限度額', 150000, '2026-01-01', '通勤手当の非課税限度額（月額）');
+
+-- ========================================
+-- 初期データ: 扶養家族判定条件 (2026年度)
+-- ========================================
+INSERT INTO dependent_rules (rule_type, rule_value, valid_from, description) VALUES
+('所得限度額_一般', '480000', '2026-01-01', '一般扶養親族の所得限度額（年間48万円）'),
+('所得限度額_配偶者', '480000', '2026-01-01', '配偶者の所得限度額（年間48万円）'),
+('所得限度額_配偶者特別', '1330000', '2026-01-01', '配偶者特別控除の所得限度額（年間133万円）'),
+('年齢_特定扶養親族', '19-23', '2026-01-01', '特定扶養親族の年齢範囲（19歳以上23歳未満）'),
+('年齢_老人扶養親族', '70-', '2026-01-01', '老人扶養親族の年齢（70歳以上）');
diff --git a/backend/sql/payroll_migration_20260119.sql b/backend/sql/payroll_migration_20260119.sql
new file mode 100644
index 0000000..50cd425
--- /dev/null
+++ b/backend/sql/payroll_migration_20260119.sql
@@ -0,0 +1,172 @@
+-- ========================================
+-- 給与システム マイグレーション 2026-01-19
+-- Payroll System Migration Script
+-- ========================================
+-- このスクリプトは既存のpayroll_schema.sqlを適用済みのDBに対して実行してください
+-- This script should be run on databases that already have payroll_schema.sql applied
+
+-- ========================================
+-- 1. 既存テーブルへの列追加
+-- ========================================
+
+-- 従業員テーブルに新しい列を追加（介護保険判定用）
+-- Add new columns to employees table (for care insurance determination)
+ALTER TABLE employees 
+ADD COLUMN IF NOT EXISTS birth_date DATE,
+ADD COLUMN IF NOT EXISTS gender VARCHAR(10),
+ADD COLUMN IF NOT EXISTS postal_code VARCHAR(10),
+ADD COLUMN IF NOT EXISTS address VARCHAR(200);
+
+COMMENT ON COLUMN employees.birth_date IS '生年月日（介護保険料計算に使用）';
+COMMENT ON COLUMN employees.gender IS '性別';
+COMMENT ON COLUMN employees.postal_code IS '郵便番号';
+COMMENT ON COLUMN employees.address IS '住所';
+
+-- 月次給与計算テーブルに介護保険列を追加
+-- Add care insurance column to monthly payroll table
+ALTER TABLE monthly_payroll 
+ADD COLUMN IF NOT EXISTS care_insurance DECIMAL(12, 2) DEFAULT 0;
+
+COMMENT ON COLUMN monthly_payroll.care_insurance IS '介護保険料（40歳以上65歳未満対象）';
+
+-- ========================================
+-- 2. 介護保険料率の初期データを追加（まだ存在しない場合）
+-- ========================================
+INSERT INTO insurance_rates (rate_type, employee_rate, employer_rate, valid_from, notes)
+SELECT '介護保険', 0.0091, 0.0091, '2026-01-01', '介護保険料率 1.82% (労使折半、40歳以上対象)'
+WHERE NOT EXISTS (
+    SELECT 1 FROM insurance_rates 
+    WHERE rate_type = '介護保険' AND valid_from = '2026-01-01'
+);
+
+-- ========================================
+-- 3. 新テーブル作成: 社会保険料上限設定
+-- ========================================
+CREATE TABLE IF NOT EXISTS insurance_limit_settings (
+    limit_id SERIAL PRIMARY KEY,
+    setting_type VARCHAR(50) NOT NULL, -- 健康保険上限/厚生年金上限/通勤手当非課税限度額
+    limit_amount DECIMAL(12, 2) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE insurance_limit_settings IS '社会保険料上限設定';
+COMMENT ON COLUMN insurance_limit_settings.setting_type IS '設定種別: 健康保険標準報酬月額上限/厚生年金標準報酬月額上限/通勤手当非課税限度額';
+COMMENT ON COLUMN insurance_limit_settings.limit_amount IS '上限額';
+
+-- ========================================
+-- 4. 新テーブル作成: 賞与計算
+-- ========================================
+CREATE TABLE IF NOT EXISTS bonus_payments (
+    bonus_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id),
+    bonus_year INTEGER NOT NULL,
+    bonus_month INTEGER NOT NULL,
+    bonus_type VARCHAR(50) NOT NULL, -- 夏季賞与/冬季賞与/決算賞与/その他
+    payment_date DATE NOT NULL,
+    status VARCHAR(20) DEFAULT 'draft', -- draft/calculated/approved/paid
+    
+    -- 支給項目
+    base_bonus DECIMAL(12, 2) DEFAULT 0, -- 基本賞与額
+    performance_bonus DECIMAL(12, 2) DEFAULT 0, -- 業績賞与
+    other_bonus DECIMAL(12, 2) DEFAULT 0, -- その他賞与
+    total_bonus DECIMAL(12, 2) DEFAULT 0, -- 総支給額
+    
+    -- 控除項目
+    health_insurance DECIMAL(12, 2) DEFAULT 0,
+    care_insurance DECIMAL(12, 2) DEFAULT 0, -- 介護保険（40歳以上）
+    pension_insurance DECIMAL(12, 2) DEFAULT 0,
+    employment_insurance DECIMAL(12, 2) DEFAULT 0,
+    income_tax DECIMAL(12, 2) DEFAULT 0, -- 賞与所得税
+    other_deduction DECIMAL(12, 2) DEFAULT 0,
+    total_deduction DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 差引支給額
+    net_bonus DECIMAL(12, 2) DEFAULT 0,
+    
+    notes TEXT,
+    calculated_at TIMESTAMP,
+    calculated_by VARCHAR(100),
+    approved_at TIMESTAMP,
+    approved_by VARCHAR(100),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    
+    CONSTRAINT uc_bonus_employee_payment UNIQUE (employee_id, bonus_year, bonus_month, bonus_type)
+);
+
+COMMENT ON TABLE bonus_payments IS '賞与計算';
+COMMENT ON COLUMN bonus_payments.bonus_type IS '賞与種別: 夏季賞与/冬季賞与/決算賞与/その他';
+COMMENT ON COLUMN bonus_payments.status IS 'ステータス: draft/calculated/approved/paid';
+
+-- ========================================
+-- 5. 新テーブル作成: 扶養家族判定条件
+-- ========================================
+CREATE TABLE IF NOT EXISTS dependent_rules (
+    rule_id SERIAL PRIMARY KEY,
+    rule_type VARCHAR(50) NOT NULL, -- 所得限度額/年齢条件/同一生計
+    rule_value VARCHAR(100) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    description TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE dependent_rules IS '扶養家族判定条件';
+COMMENT ON COLUMN dependent_rules.rule_type IS 'ルール種別: 所得限度額/年齢条件/同一生計';
+
+-- ========================================
+-- 6. インデックス作成
+-- ========================================
+CREATE INDEX IF NOT EXISTS idx_insurance_limits_valid ON insurance_limit_settings(valid_from, valid_to);
+CREATE INDEX IF NOT EXISTS idx_bonus_employee_year ON bonus_payments(employee_id, bonus_year);
+CREATE INDEX IF NOT EXISTS idx_bonus_status ON bonus_payments(status);
+CREATE INDEX IF NOT EXISTS idx_dependent_rules_valid ON dependent_rules(valid_from, valid_to);
+
+-- ========================================
+-- 7. トリガー: 更新日時の自動更新
+-- ========================================
+CREATE TRIGGER trg_insurance_limits_updated_at BEFORE UPDATE ON insurance_limit_settings
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_bonus_payments_updated_at BEFORE UPDATE ON bonus_payments
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+-- ========================================
+-- 8. 初期データ: 社会保険料上限設定 (2026年度)
+-- ========================================
+INSERT INTO insurance_limit_settings (setting_type, limit_amount, valid_from, notes) VALUES
+('健康保険標準報酬月額上限', 1390000, '2026-01-01', '健康保険の標準報酬月額上限（第50級）'),
+('厚生年金標準報酬月額上限', 650000, '2026-01-01', '厚生年金保険の標準報酬月額上限（第32級）'),
+('通勤手当非課税限度額', 150000, '2026-01-01', '通勤手当の非課税限度額（月額）')
+ON CONFLICT DO NOTHING;
+
+-- ========================================
+-- 9. 初期データ: 扶養家族判定条件 (2026年度)
+-- ========================================
+INSERT INTO dependent_rules (rule_type, rule_value, valid_from, description) VALUES
+('所得限度額_一般', '480000', '2026-01-01', '一般扶養親族の所得限度額（年間48万円）'),
+('所得限度額_配偶者', '480000', '2026-01-01', '配偶者の所得限度額（年間48万円）'),
+('所得限度額_配偶者特別', '1330000', '2026-01-01', '配偶者特別控除の所得限度額（年間133万円）'),
+('年齢_特定扶養親族', '19-23', '2026-01-01', '特定扶養親族の年齢範囲（19歳以上23歳未満）'),
+('年齢_老人扶養親族', '70-', '2026-01-01', '老人扶養親族の年齢（70歳以上）')
+ON CONFLICT DO NOTHING;
+
+-- ========================================
+-- マイグレーション完了
+-- ========================================
+-- 以下のコマンドで適用状態を確認できます：
+-- Verify migration with the following commands:
+--
+-- \d employees          -- 従業員テーブルの構造確認
+-- \d monthly_payroll    -- 月次給与テーブルの構造確認
+-- \dt *bonus*           -- 賞与テーブルの確認
+-- \dt *insurance_limit* -- 保険上限テーブルの確認
+-- \dt *dependent_rule*  -- 扶養判定テーブルの確認
+--
+-- SELECT * FROM insurance_limit_settings;  -- 保険上限設定の確認
+-- SELECT * FROM dependent_rules;           -- 扶養判定条件の確認
+-- SELECT * FROM insurance_rates WHERE rate_type = '介護保険';  -- 介護保険料率の確認
diff --git a/backend/sql/payroll_schema.sql b/backend/sql/payroll_schema.sql
new file mode 100644
index 0000000..8c5e516
--- /dev/null
+++ b/backend/sql/payroll_schema.sql
@@ -0,0 +1,238 @@
+-- 給与システム用スキーマ
+-- Payroll System Schema
+
+-- ========================================
+-- 1. 従業員マスタ (Employees)
+-- ========================================
+CREATE TABLE IF NOT EXISTS employees (
+    employee_id SERIAL PRIMARY KEY,
+    employee_code VARCHAR(20) UNIQUE NOT NULL,
+    name VARCHAR(100) NOT NULL,
+    name_kana VARCHAR(100),
+    birth_date DATE, -- 生年月日（介護保険判定に使用）
+    gender VARCHAR(10), -- 性別
+    email VARCHAR(100),
+    phone VARCHAR(20),
+    postal_code VARCHAR(10), -- 郵便番号
+    address VARCHAR(200), -- 住所
+    hire_date DATE NOT NULL,
+    termination_date DATE,
+    is_active BOOLEAN DEFAULT true,
+    bank_name VARCHAR(100),
+    bank_branch VARCHAR(100),
+    bank_account_number VARCHAR(20),
+    bank_account_type VARCHAR(20), -- 普通/当座
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE employees IS '従業員マスタ';
+COMMENT ON COLUMN employees.employee_code IS '従業員コード';
+COMMENT ON COLUMN employees.birth_date IS '生年月日（介護保険料計算に使用）';
+COMMENT ON COLUMN employees.gender IS '性別';
+COMMENT ON COLUMN employees.bank_account_type IS '口座種別: 普通/当座';
+
+-- ========================================
+-- 2. 扶養家族情報 (Dependents)
+-- ========================================
+CREATE TABLE IF NOT EXISTS dependents (
+    dependent_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id) ON DELETE CASCADE,
+    name VARCHAR(100) NOT NULL,
+    relationship VARCHAR(20) NOT NULL, -- 配偶者/子/親/その他
+    birth_date DATE,
+    is_spouse BOOLEAN DEFAULT false,
+    is_disabled BOOLEAN DEFAULT false, -- 障害者控除対象
+    income_amount DECIMAL(12, 2) DEFAULT 0, -- 年間所得
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE dependents IS '扶養家族情報';
+COMMENT ON COLUMN dependents.relationship IS '続柄: 配偶者/子/親/その他';
+COMMENT ON COLUMN dependents.is_disabled IS '障害者控除対象フラグ';
+COMMENT ON COLUMN dependents.income_amount IS '年間所得額';
+
+-- ========================================
+-- 3. 給与基本設定 (Salary Settings)
+-- ========================================
+CREATE TABLE IF NOT EXISTS salary_settings (
+    setting_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id) ON DELETE CASCADE,
+    base_salary DECIMAL(12, 2) NOT NULL DEFAULT 0,
+    hourly_rate DECIMAL(10, 2),
+    employment_type VARCHAR(20) NOT NULL, -- 正社員/契約社員/パート/アルバイト
+    payment_type VARCHAR(20) NOT NULL, -- 月給/時給/日給
+    commute_allowance DECIMAL(12, 2) DEFAULT 0,
+    other_allowance DECIMAL(12, 2) DEFAULT 0,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT uc_employee_valid_from UNIQUE (employee_id, valid_from)
+);
+
+COMMENT ON TABLE salary_settings IS '給与基本設定';
+COMMENT ON COLUMN salary_settings.employment_type IS '雇用形態: 正社員/契約社員/パート/アルバイト';
+COMMENT ON COLUMN salary_settings.payment_type IS '支給形態: 月給/時給/日給';
+
+-- ========================================
+-- 4. 社会保険料率マスタ (Insurance Rates)
+-- ========================================
+CREATE TABLE IF NOT EXISTS insurance_rates (
+    rate_id SERIAL PRIMARY KEY,
+    rate_type VARCHAR(50) NOT NULL, -- 健康保険/厚生年金/雇用保険/労災保険
+    employee_rate DECIMAL(6, 4) NOT NULL, -- 従業員負担率
+    employer_rate DECIMAL(6, 4) NOT NULL, -- 会社負担率
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE insurance_rates IS '社会保険料率マスタ';
+COMMENT ON COLUMN insurance_rates.rate_type IS '保険種類: 健康保険/厚生年金/雇用保険/労災保険';
+COMMENT ON COLUMN insurance_rates.employee_rate IS '従業員負担率';
+COMMENT ON COLUMN insurance_rates.employer_rate IS '会社負担率';
+
+-- ========================================
+-- 5. 所得税率表 (Income Tax Table)
+-- ========================================
+CREATE TABLE IF NOT EXISTS income_tax_table (
+    tax_id SERIAL PRIMARY KEY,
+    monthly_income_from DECIMAL(12, 2) NOT NULL,
+    monthly_income_to DECIMAL(12, 2) NOT NULL,
+    dependents_count INTEGER NOT NULL DEFAULT 0, -- 扶養家族人数
+    tax_amount DECIMAL(10, 2) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE income_tax_table IS '源泉所得税額表';
+COMMENT ON COLUMN income_tax_table.dependents_count IS '扶養家族人数';
+
+-- ========================================
+-- 6. 月次給与計算ヘッダー (Monthly Payroll Header)
+-- ========================================
+CREATE TABLE IF NOT EXISTS monthly_payroll (
+    payroll_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id),
+    payroll_year INTEGER NOT NULL,
+    payroll_month INTEGER NOT NULL,
+    payment_date DATE NOT NULL,
+    status VARCHAR(20) DEFAULT 'draft', -- draft/calculated/approved/paid
+    
+    -- 勤怠情報
+    working_days DECIMAL(5, 2) DEFAULT 0,
+    working_hours DECIMAL(6, 2) DEFAULT 0,
+    overtime_hours DECIMAL(6, 2) DEFAULT 0,
+    holiday_hours DECIMAL(6, 2) DEFAULT 0,
+    late_hours DECIMAL(6, 2) DEFAULT 0,
+    absent_days DECIMAL(5, 2) DEFAULT 0,
+    
+    -- 支給項目
+    base_salary DECIMAL(12, 2) DEFAULT 0,
+    overtime_pay DECIMAL(12, 2) DEFAULT 0,
+    holiday_pay DECIMAL(12, 2) DEFAULT 0,
+    commute_allowance DECIMAL(12, 2) DEFAULT 0,
+    other_allowance DECIMAL(12, 2) DEFAULT 0,
+    total_payment DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 控除項目
+    health_insurance DECIMAL(12, 2) DEFAULT 0,
+    care_insurance DECIMAL(12, 2) DEFAULT 0, -- 介護保険（40歳以上）
+    pension_insurance DECIMAL(12, 2) DEFAULT 0,
+    employment_insurance DECIMAL(12, 2) DEFAULT 0,
+    income_tax DECIMAL(12, 2) DEFAULT 0,
+    resident_tax DECIMAL(12, 2) DEFAULT 0,
+    other_deduction DECIMAL(12, 2) DEFAULT 0,
+    total_deduction DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 差引支給額
+    net_payment DECIMAL(12, 2) DEFAULT 0,
+    
+    notes TEXT,
+    calculated_at TIMESTAMP,
+    calculated_by VARCHAR(100),
+    approved_at TIMESTAMP,
+    approved_by VARCHAR(100),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    
+    CONSTRAINT uc_payroll_employee_month UNIQUE (employee_id, payroll_year, payroll_month)
+);
+
+COMMENT ON TABLE monthly_payroll IS '月次給与計算';
+COMMENT ON COLUMN monthly_payroll.status IS 'ステータス: draft/calculated/approved/paid';
+
+-- ========================================
+-- 7. 給与明細項目詳細 (Payroll Detail Items)
+-- ========================================
+CREATE TABLE IF NOT EXISTS payroll_details (
+    detail_id SERIAL PRIMARY KEY,
+    payroll_id INTEGER NOT NULL REFERENCES monthly_payroll(payroll_id) ON DELETE CASCADE,
+    item_type VARCHAR(20) NOT NULL, -- payment/deduction
+    item_code VARCHAR(50) NOT NULL,
+    item_name VARCHAR(100) NOT NULL,
+    amount DECIMAL(12, 2) NOT NULL,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE payroll_details IS '給与明細項目詳細';
+COMMENT ON COLUMN payroll_details.item_type IS '項目区分: payment/deduction';
+
+-- ========================================
+-- インデックス作成
+-- ========================================
+CREATE INDEX idx_employees_code ON employees(employee_code);
+CREATE INDEX idx_employees_active ON employees(is_active);
+CREATE INDEX idx_dependents_employee ON dependents(employee_id);
+CREATE INDEX idx_salary_settings_employee ON salary_settings(employee_id);
+CREATE INDEX idx_salary_settings_valid ON salary_settings(valid_from, valid_to);
+CREATE INDEX idx_insurance_rates_valid ON insurance_rates(valid_from, valid_to);
+CREATE INDEX idx_income_tax_valid ON income_tax_table(valid_from, valid_to);
+CREATE INDEX idx_payroll_employee_year_month ON monthly_payroll(employee_id, payroll_year, payroll_month);
+CREATE INDEX idx_payroll_status ON monthly_payroll(status);
+CREATE INDEX idx_payroll_details_payroll ON payroll_details(payroll_id);
+
+-- ========================================
+-- トリガー: 更新日時の自動更新
+-- ========================================
+CREATE OR REPLACE FUNCTION update_updated_at()
+RETURNS TRIGGER AS $$
+BEGIN
+    NEW.updated_at = CURRENT_TIMESTAMP;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER trg_employees_updated_at BEFORE UPDATE ON employees
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_dependents_updated_at BEFORE UPDATE ON dependents
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_salary_settings_updated_at BEFORE UPDATE ON salary_settings
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_insurance_rates_updated_at BEFORE UPDATE ON insurance_rates
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_monthly_payroll_updated_at BEFORE UPDATE ON monthly_payroll
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+-- ========================================
+-- 初期データ: 保険料率 (2026年度)
+-- ========================================
+INSERT INTO insurance_rates (rate_type, employee_rate, employer_rate, valid_from, notes) VALUES
+('健康保険', 0.0500, 0.0500, '2026-01-01', '健康保険料率 10.00% (労使折半)'),
+('介護保険', 0.0091, 0.0091, '2026-01-01', '介護保険料率 1.82% (労使折半、40歳以上対象)'),
+('厚生年金', 0.0915, 0.0915, '2026-01-01', '厚生年金保険料率 18.30% (労使折半)'),
+('雇用保険', 0.0060, 0.0095, '2026-01-01', '雇用保険料率 従業員0.6% 事業主0.95%'),
+('労災保険', 0.0000, 0.0030, '2026-01-01', '労災保険料率 事業主のみ0.3%');
diff --git a/backend/sql/payroll_schema_complete.sql b/backend/sql/payroll_schema_complete.sql
new file mode 100644
index 0000000..4341190
--- /dev/null
+++ b/backend/sql/payroll_schema_complete.sql
@@ -0,0 +1,436 @@
+-- ========================================
+-- 給与システム 完全版スキーマ
+-- Payroll System Complete Schema
+-- ========================================
+-- このスクリプトは既存のテーブルを削除して再作成します
+-- This script will DROP existing tables and recreate them
+-- 
+-- 警告: すべてのデータが失われます！
+-- WARNING: ALL DATA WILL BE LOST!
+-- ========================================
+
+-- ========================================
+-- テーブル削除（依存関係の逆順）
+-- ========================================
+DROP TABLE IF EXISTS payroll_details CASCADE;
+DROP TABLE IF EXISTS monthly_payroll CASCADE;
+DROP TABLE IF EXISTS bonus_payments CASCADE;
+DROP TABLE IF EXISTS income_tax_table CASCADE;
+DROP TABLE IF EXISTS child_support_contribution_rates CASCADE;
+DROP TABLE IF EXISTS insurance_rates CASCADE;
+DROP TABLE IF EXISTS insurance_limit_settings CASCADE;
+DROP TABLE IF EXISTS dependent_rules CASCADE;
+DROP TABLE IF EXISTS salary_settings CASCADE;
+DROP TABLE IF EXISTS dependents CASCADE;
+DROP TABLE IF EXISTS employees CASCADE;
+
+-- ========================================
+-- 関数削除
+-- ========================================
+DROP FUNCTION IF EXISTS update_updated_at() CASCADE;
+
+-- ========================================
+-- 1. 従業員マスタ (Employees)
+-- ========================================
+CREATE TABLE employees (
+    employee_id SERIAL PRIMARY KEY,
+    employee_code VARCHAR(20) UNIQUE NOT NULL,
+    name VARCHAR(100) NOT NULL,
+    name_kana VARCHAR(100),
+    birth_date DATE, -- 生年月日（介護保険判定に使用）
+    gender VARCHAR(10), -- 性別
+    email VARCHAR(100),
+    phone VARCHAR(20),
+    postal_code VARCHAR(10), -- 郵便番号
+    address VARCHAR(200), -- 住所
+    hire_date DATE NOT NULL,
+    termination_date DATE,
+    is_active BOOLEAN DEFAULT true,
+    bank_name VARCHAR(100),
+    bank_branch VARCHAR(100),
+    bank_account_number VARCHAR(20),
+    bank_account_type VARCHAR(20), -- 普通/当座
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE employees IS '従業員マスタ';
+COMMENT ON COLUMN employees.employee_code IS '従業員コード';
+COMMENT ON COLUMN employees.birth_date IS '生年月日（介護保険料計算に使用）';
+COMMENT ON COLUMN employees.gender IS '性別';
+COMMENT ON COLUMN employees.postal_code IS '郵便番号';
+COMMENT ON COLUMN employees.address IS '住所';
+COMMENT ON COLUMN employees.bank_account_type IS '口座種別: 普通/当座';
+
+-- ========================================
+-- 2. 扶養家族情報 (Dependents)
+-- ========================================
+CREATE TABLE dependents (
+    dependent_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id) ON DELETE CASCADE,
+    name VARCHAR(100) NOT NULL,
+    relationship VARCHAR(20) NOT NULL, -- 配偶者/子/親/その他
+    birth_date DATE,
+    is_spouse BOOLEAN DEFAULT false,
+    is_disabled BOOLEAN DEFAULT false, -- 障害者控除対象
+    income_amount DECIMAL(12, 2) DEFAULT 0, -- 年間所得
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE dependents IS '扶養家族情報';
+COMMENT ON COLUMN dependents.relationship IS '続柄: 配偶者/子/親/その他';
+COMMENT ON COLUMN dependents.is_disabled IS '障害者控除対象フラグ';
+COMMENT ON COLUMN dependents.income_amount IS '年間所得額';
+
+-- ========================================
+-- 3. 給与基本設定 (Salary Settings)
+-- ========================================
+CREATE TABLE salary_settings (
+    setting_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id) ON DELETE CASCADE,
+    base_salary DECIMAL(12, 2) NOT NULL DEFAULT 0,
+    hourly_rate DECIMAL(10, 2),
+    employment_type VARCHAR(20) NOT NULL, -- 正社員/契約社員/パート/アルバイト
+    payment_type VARCHAR(20) NOT NULL, -- 月給/時給/日給
+    commute_allowance DECIMAL(12, 2) DEFAULT 0,
+    other_allowance DECIMAL(12, 2) DEFAULT 0,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT uc_employee_valid_from UNIQUE (employee_id, valid_from)
+);
+
+COMMENT ON TABLE salary_settings IS '給与基本設定';
+COMMENT ON COLUMN salary_settings.employment_type IS '雇用形態: 正社員/契約社員/パート/アルバイト';
+COMMENT ON COLUMN salary_settings.payment_type IS '支給形態: 月給/時給/日給';
+
+-- ========================================
+-- 4. 社会保険料率マスタ (Insurance Rates)
+-- ========================================
+CREATE TABLE insurance_rates (
+    rate_id SERIAL PRIMARY KEY,
+    rate_year INTEGER NOT NULL, -- 適用年度（例：2026）
+    rate_type VARCHAR(50) NOT NULL, -- 健康保険/介護保険/厚生年金/雇用保険/労災保険
+    calculation_target VARCHAR(20) NOT NULL, -- 給与/賞与
+    prefecture VARCHAR(50) DEFAULT '東京都', -- 事業所所在地（東京都/神奈川県/千葉県/埼玉県）
+    employee_rate DECIMAL(6, 4) NOT NULL, -- 従業員負担率
+    employer_rate DECIMAL(6, 4) NOT NULL, -- 会社負担率
+    care_insurance_age_threshold INTEGER DEFAULT 40, -- 介護保険適用年齢下限
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT uc_rate_year_type_target_prefecture UNIQUE (rate_year, rate_type, calculation_target, prefecture)
+);
+
+COMMENT ON TABLE insurance_rates IS '社会保険料率マスタ';
+COMMENT ON COLUMN insurance_rates.rate_year IS '適用年度';
+COMMENT ON COLUMN insurance_rates.rate_type IS '保険種類: 健康保険/介護保険/厚生年金/雇用保険/労災保険';
+COMMENT ON COLUMN insurance_rates.calculation_target IS '計算対象: 給与/賞与';
+COMMENT ON COLUMN insurance_rates.prefecture IS '事業所所在地';
+COMMENT ON COLUMN insurance_rates.employee_rate IS '従業員負担率';
+COMMENT ON COLUMN insurance_rates.employer_rate IS '会社負担率';
+COMMENT ON COLUMN insurance_rates.care_insurance_age_threshold IS '介護保険適用年齢下限（この年齢以上が対象）';
+
+-- ========================================
+-- 4-2. 子ども・子育て拠出金率 (Child Support Contribution Rates)
+-- ========================================
+CREATE TABLE child_support_contribution_rates (
+    contribution_id SERIAL PRIMARY KEY,
+    rate_year INTEGER NOT NULL, -- 適用年度
+    income_threshold DECIMAL(12, 2) NOT NULL, -- 所得基準額（標準報酬月額）
+    contribution_rate DECIMAL(6, 4) NOT NULL, -- 拠出金率（事業主負担のみ）
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT uc_contribution_year UNIQUE (rate_year)
+);
+
+COMMENT ON TABLE child_support_contribution_rates IS '子ども・子育て拠出金率';
+COMMENT ON COLUMN child_support_contribution_rates.rate_year IS '適用年度';
+COMMENT ON COLUMN child_support_contribution_rates.income_threshold IS '所得基準額（標準報酬月額の上限）';
+COMMENT ON COLUMN child_support_contribution_rates.contribution_rate IS '拠出金率（事業主のみ負担）';
+
+-- ========================================
+-- 5. 社会保険料上限設定 (Insurance Limit Settings)
+-- ========================================
+CREATE TABLE insurance_limit_settings (
+    limit_id SERIAL PRIMARY KEY,
+    setting_type VARCHAR(50) NOT NULL, -- 健康保険標準報酬月額上限/厚生年金標準報酬月額上限/通勤手当非課税限度額
+    limit_amount DECIMAL(12, 2) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE insurance_limit_settings IS '社会保険料上限設定';
+COMMENT ON COLUMN insurance_limit_settings.setting_type IS '設定種別: 健康保険標準報酬月額上限/厚生年金標準報酬月額上限/通勤手当非課税限度額';
+COMMENT ON COLUMN insurance_limit_settings.limit_amount IS '上限額';
+
+-- ========================================
+-- 6. 扶養家族判定条件 (Dependent Rules)
+-- ========================================
+CREATE TABLE dependent_rules (
+    rule_id SERIAL PRIMARY KEY,
+    rule_type VARCHAR(50) NOT NULL, -- 所得限度額/年齢条件/同一生計
+    rule_value VARCHAR(100) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    description TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE dependent_rules IS '扶養家族判定条件';
+COMMENT ON COLUMN dependent_rules.rule_type IS 'ルール種別: 所得限度額/年齢条件/同一生計';
+
+-- ========================================
+-- 7. 所得税率表 (Income Tax Table)
+-- ========================================
+CREATE TABLE income_tax_table (
+    tax_id SERIAL PRIMARY KEY,
+    monthly_income_from DECIMAL(12, 2) NOT NULL,
+    monthly_income_to DECIMAL(12, 2) NOT NULL,
+    dependents_count INTEGER NOT NULL DEFAULT 0, -- 扶養家族人数
+    tax_amount DECIMAL(10, 2) NOT NULL,
+    valid_from DATE NOT NULL,
+    valid_to DATE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE income_tax_table IS '源泉所得税額表';
+COMMENT ON COLUMN income_tax_table.dependents_count IS '扶養家族人数';
+
+-- ========================================
+-- 8. 月次給与計算 (Monthly Payroll)
+-- ========================================
+CREATE TABLE monthly_payroll (
+    payroll_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id),
+    payroll_year INTEGER NOT NULL,
+    payroll_month INTEGER NOT NULL,
+    payment_date DATE NOT NULL,
+    status VARCHAR(20) DEFAULT 'draft', -- draft/calculated/approved/paid
+    
+    -- 勤怠情報
+    working_days DECIMAL(5, 2) DEFAULT 0,
+    working_hours DECIMAL(6, 2) DEFAULT 0,
+    overtime_hours DECIMAL(6, 2) DEFAULT 0,
+    holiday_hours DECIMAL(6, 2) DEFAULT 0,
+    late_hours DECIMAL(6, 2) DEFAULT 0,
+    absent_days DECIMAL(5, 2) DEFAULT 0,
+    
+    -- 支給項目
+    base_salary DECIMAL(12, 2) DEFAULT 0,
+    overtime_pay DECIMAL(12, 2) DEFAULT 0,
+    holiday_pay DECIMAL(12, 2) DEFAULT 0,
+    commute_allowance DECIMAL(12, 2) DEFAULT 0,
+    other_allowance DECIMAL(12, 2) DEFAULT 0,
+    total_payment DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 控除項目
+    health_insurance DECIMAL(12, 2) DEFAULT 0,
+    care_insurance DECIMAL(12, 2) DEFAULT 0, -- 介護保険（40歳以上65歳未満）
+    pension_insurance DECIMAL(12, 2) DEFAULT 0,
+    employment_insurance DECIMAL(12, 2) DEFAULT 0,
+    income_tax DECIMAL(12, 2) DEFAULT 0,
+    resident_tax DECIMAL(12, 2) DEFAULT 0,
+    other_deduction DECIMAL(12, 2) DEFAULT 0,
+    total_deduction DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 差引支給額
+    net_payment DECIMAL(12, 2) DEFAULT 0,
+    
+    notes TEXT,
+    calculated_at TIMESTAMP,
+    calculated_by VARCHAR(100),
+    approved_at TIMESTAMP,
+    approved_by VARCHAR(100),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    
+    CONSTRAINT uc_payroll_employee_month UNIQUE (employee_id, payroll_year, payroll_month)
+);
+
+COMMENT ON TABLE monthly_payroll IS '月次給与計算';
+COMMENT ON COLUMN monthly_payroll.status IS 'ステータス: draft/calculated/approved/paid';
+COMMENT ON COLUMN monthly_payroll.care_insurance IS '介護保険料（40歳以上65歳未満対象）';
+
+-- ========================================
+-- 9. 賞与計算 (Bonus Payments)
+-- ========================================
+CREATE TABLE bonus_payments (
+    bonus_id SERIAL PRIMARY KEY,
+    employee_id INTEGER NOT NULL REFERENCES employees(employee_id),
+    bonus_year INTEGER NOT NULL,
+    bonus_month INTEGER NOT NULL,
+    bonus_type VARCHAR(50) NOT NULL, -- 夏季賞与/冬季賞与/決算賞与/その他
+    payment_date DATE NOT NULL,
+    status VARCHAR(20) DEFAULT 'draft', -- draft/calculated/approved/paid
+    
+    -- 支給項目
+    base_bonus DECIMAL(12, 2) DEFAULT 0, -- 基本賞与額
+    performance_bonus DECIMAL(12, 2) DEFAULT 0, -- 業績賞与
+    other_bonus DECIMAL(12, 2) DEFAULT 0, -- その他賞与
+    total_bonus DECIMAL(12, 2) DEFAULT 0, -- 総支給額
+    
+    -- 控除項目
+    health_insurance DECIMAL(12, 2) DEFAULT 0,
+    care_insurance DECIMAL(12, 2) DEFAULT 0, -- 介護保険（40歳以上65歳未満）
+    pension_insurance DECIMAL(12, 2) DEFAULT 0,
+    employment_insurance DECIMAL(12, 2) DEFAULT 0,
+    income_tax DECIMAL(12, 2) DEFAULT 0, -- 賞与所得税
+    other_deduction DECIMAL(12, 2) DEFAULT 0,
+    total_deduction DECIMAL(12, 2) DEFAULT 0,
+    
+    -- 差引支給額
+    net_bonus DECIMAL(12, 2) DEFAULT 0,
+    
+    notes TEXT,
+    calculated_at TIMESTAMP,
+    calculated_by VARCHAR(100),
+    approved_at TIMESTAMP,
+    approved_by VARCHAR(100),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    
+    CONSTRAINT uc_bonus_employee_payment UNIQUE (employee_id, bonus_year, bonus_month, bonus_type)
+);
+
+COMMENT ON TABLE bonus_payments IS '賞与計算';
+COMMENT ON COLUMN bonus_payments.bonus_type IS '賞与種別: 夏季賞与/冬季賞与/決算賞与/その他';
+COMMENT ON COLUMN bonus_payments.status IS 'ステータス: draft/calculated/approved/paid';
+
+-- ========================================
+-- 10. 給与明細項目詳細 (Payroll Detail Items)
+-- ========================================
+CREATE TABLE payroll_details (
+    detail_id SERIAL PRIMARY KEY,
+    payroll_id INTEGER NOT NULL REFERENCES monthly_payroll(payroll_id) ON DELETE CASCADE,
+    item_type VARCHAR(20) NOT NULL, -- payment/deduction
+    item_code VARCHAR(50) NOT NULL,
+    item_name VARCHAR(100) NOT NULL,
+    amount DECIMAL(12, 2) NOT NULL,
+    notes TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+COMMENT ON TABLE payroll_details IS '給与明細項目詳細';
+COMMENT ON COLUMN payroll_details.item_type IS '項目区分: payment/deduction';
+
+-- ========================================
+-- インデックス作成
+-- ========================================
+CREATE INDEX idx_employees_code ON employees(employee_code);
+CREATE INDEX idx_employees_active ON employees(is_active);
+CREATE INDEX idx_dependents_employee ON dependents(employee_id);
+CREATE INDEX idx_salary_settings_employee ON salary_settings(employee_id);
+CREATE INDEX idx_salary_settings_valid ON salary_settings(valid_from, valid_to);
+CREATE INDEX idx_insurance_rates_year ON insurance_rates(rate_year, rate_type, calculation_target);
+CREATE INDEX idx_child_support_year ON child_support_contribution_rates(rate_year);
+CREATE INDEX idx_insurance_limits_valid ON insurance_limit_settings(valid_from, valid_to);
+CREATE INDEX idx_dependent_rules_valid ON dependent_rules(valid_from, valid_to);
+CREATE INDEX idx_income_tax_valid ON income_tax_table(valid_from, valid_to);
+CREATE INDEX idx_payroll_employee_year_month ON monthly_payroll(employee_id, payroll_year, payroll_month);
+CREATE INDEX idx_payroll_status ON monthly_payroll(status);
+CREATE INDEX idx_bonus_employee_year ON bonus_payments(employee_id, bonus_year);
+CREATE INDEX idx_bonus_status ON bonus_payments(status);
+CREATE INDEX idx_payroll_details_payroll ON payroll_details(payroll_id);
+
+-- ========================================
+-- トリガー関数: 更新日時の自動更新
+-- ========================================
+CREATE OR REPLACE FUNCTION update_updated_at()
+RETURNS TRIGGER AS $$
+BEGIN
+    NEW.updated_at = CURRENT_TIMESTAMP;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+-- ========================================
+-- トリガー設定
+-- ========================================
+CREATE TRIGGER trg_employees_updated_at BEFORE UPDATE ON employees
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_dependents_updated_at BEFORE UPDATE ON dependents
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_salary_settings_updated_at BEFORE UPDATE ON salary_settings
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_insurance_rates_updated_at BEFORE UPDATE ON insurance_rates
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_child_support_updated_at BEFORE UPDATE ON child_support_contribution_rates
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_insurance_limits_updated_at BEFORE UPDATE ON insurance_limit_settings
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_monthly_payroll_updated_at BEFORE UPDATE ON monthly_payroll
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+CREATE TRIGGER trg_bonus_payments_updated_at BEFORE UPDATE ON bonus_payments
+    FOR EACH ROW EXECUTE FUNCTION update_updated_at();
+
+-- ========================================
+-- 初期データ: 社会保険料率 (2026年度) - 給与計算用
+-- ========================================
+-- 東京都の健康保険料率（給与）
+INSERT INTO insurance_rates (rate_year, rate_type, calculation_target, prefecture, employee_rate, employer_rate, care_insurance_age_threshold, notes) VALUES
+(2026, '健康保険', '給与', '東京都', 0.0500, 0.0500, 40, '健康保険料率 10.00% (労使折半) - 給与'),
+(2026, '介護保険', '給与', '東京都', 0.0091, 0.0091, 40, '介護保険料率 1.82% (労使折半、40歳以上対象) - 給与'),
+(2026, '厚生年金', '給与', '東京都', 0.0915, 0.0915, NULL, '厚生年金保険料率 18.30% (労使折半) - 給与'),
+(2026, '雇用保険', '給与', '東京都', 0.0060, 0.0095, NULL, '雇用保険料率 従業員0.6% 事業主0.95% - 給与'),
+(2026, '労災保険', '給与', '東京都', 0.0000, 0.0030, NULL, '労災保険料率 事業主のみ0.3% - 給与');
+
+-- 東京都の健康保険料率（賞与）
+INSERT INTO insurance_rates (rate_year, rate_type, calculation_target, prefecture, employee_rate, employer_rate, care_insurance_age_threshold, notes) VALUES
+(2026, '健康保険', '賞与', '東京都', 0.0500, 0.0500, 40, '健康保険料率 10.00% (労使折半) - 賞与'),
+(2026, '介護保険', '賞与', '東京都', 0.0091, 0.0091, 40, '介護保険料率 1.82% (労使折半、40歳以上対象) - 賞与'),
+(2026, '厚生年金', '賞与', '東京都', 0.0915, 0.0915, NULL, '厚生年金保険料率 18.30% (労使折半) - 賞与'),
+(2026, '雇用保険', '賞与', '東京都', 0.0060, 0.0095, NULL, '雇用保険料率 従業員0.6% 事業主0.95% - 賞与');
+
+-- ========================================
+-- 初期データ: 子ども・子育て拠出金率 (2026年度)
+-- ========================================
+INSERT INTO child_support_contribution_rates (rate_year, income_threshold, contribution_rate, notes) VALUES
+(2026, 1500000, 0.0036, '子ども・子育て拠出金率 0.36% (事業主のみ負担、標準報酬月額150万円まで)');
+
+-- ========================================
+-- 初期データ: 社会保険料上限設定 (2026年度)
+-- ========================================
+INSERT INTO insurance_limit_settings (setting_type, limit_amount, valid_from, notes) VALUES
+('健康保険標準報酬月額上限', 1390000, '2026-01-01', '健康保険の標準報酬月額上限（第50級）'),
+('厚生年金標準報酬月額上限', 650000, '2026-01-01', '厚生年金保険の標準報酬月額上限（第32級）'),
+('通勤手当非課税限度額', 150000, '2026-01-01', '通勤手当の非課税限度額（月額）');
+
+-- ========================================
+-- 初期データ: 扶養家族判定条件 (2026年度)
+-- ========================================
+INSERT INTO dependent_rules (rule_type, rule_value, valid_from, description) VALUES
+('所得限度額_一般', '480000', '2026-01-01', '一般扶養親族の所得限度額（年間48万円）'),
+('所得限度額_配偶者', '480000', '2026-01-01', '配偶者の所得限度額（年間48万円）'),
+('所得限度額_配偶者特別', '1330000', '2026-01-01', '配偶者特別控除の所得限度額（年間133万円）'),
+('年齢_特定扶養親族', '19-23', '2026-01-01', '特定扶養親族の年齢範囲（19歳以上23歳未満）'),
+('年齢_老人扶養親族', '70-', '2026-01-01', '老人扶養親族の年齢（70歳以上）');
+
+-- ========================================
+-- スキーマ作成完了
+-- ========================================
+-- 確認コマンド:
+-- \dt                  -- テーブル一覧
+-- \d employees         -- 従業員テーブル構造
+-- \d monthly_payroll   -- 月次給与テーブル構造
+-- \d bonus_payments    -- 賞与テーブル構造
+--
+-- SELECT * FROM insurance_rates;           -- 保険料率確認
+-- SELECT * FROM insurance_limit_settings;  -- 保険上限確認
+-- SELECT * FROM dependent_rules;           -- 扶養判定条件確認
diff --git a/backend/update_precision.py b/backend/update_precision.py
new file mode 100644
index 0000000..ecf0074
--- /dev/null
+++ b/backend/update_precision.py
@@ -0,0 +1,79 @@
+import os
+import psycopg2
+from dotenv import load_dotenv
+
+# Load environment variables
+root_env = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.env')
+load_dotenv(root_env)
+
+# Connect to database
+conn = psycopg2.connect(
+    host=os.getenv('DB_HOST', '192.168.0.61'),
+    port=os.getenv('DB_PORT', '55432'),
+    dbname=os.getenv('DB_NAME', 'njts_acct'),
+    user=os.getenv('DB_USER', 'njts_app'),
+    password=os.getenv('DB_PASSWORD')
+)
+
+cur = conn.cursor()
+
+print("保険率カラムを DECIMAL(5,3) に変更中...")
+
+# Alter insurance_rates table
+cur.execute("""
+    ALTER TABLE insurance_rates 
+    ALTER COLUMN employee_rate TYPE DECIMAL(5, 3),
+    ALTER COLUMN employer_rate TYPE DECIMAL(5, 3)
+""")
+
+# Alter child_support_contribution_rates table
+cur.execute("""
+    ALTER TABLE child_support_contribution_rates 
+    ALTER COLUMN contribution_rate TYPE DECIMAL(5, 3)
+""")
+
+conn.commit()
+
+print("OK カラム変更完了")
+
+# Verify changes
+cur.execute("""
+    SELECT column_name, data_type, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='insurance_rates' 
+    AND column_name IN ('employee_rate', 'employer_rate') 
+    ORDER BY column_name
+""")
+
+print("\n変更後の insurance_rates カラム:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: {row[1]}({row[2]},{row[3]})")
+
+cur.execute("""
+    SELECT column_name, data_type, numeric_precision, numeric_scale 
+    FROM information_schema.columns 
+    WHERE table_name='child_support_contribution_rates' 
+    AND column_name = 'contribution_rate'
+""")
+
+print("\n変更後の child_support_contribution_rates カラム:")
+for row in cur.fetchall():
+    print(f"  {row[0]}: {row[1]}({row[2]},{row[3]})")
+
+# Check data
+cur.execute("""
+    SELECT rate_year, rate_type, calculation_target, prefecture, 
+           employee_rate, employer_rate
+    FROM insurance_rates 
+    WHERE rate_year = 2025 AND rate_type = '健康保険'
+    LIMIT 3
+""")
+
+print("\n実際のデータ (2025年健康保険):")
+for row in cur.fetchall():
+    print(f"  {row[0]} {row[1]} {row[2]} {row[3]}: 従業員={float(row[4]):.3f} 会社={float(row[5]):.3f}")
+
+cur.close()
+conn.close()
+
+print("\n完了！")
diff --git a/docs/payroll_enhancements.md b/docs/payroll_enhancements.md
new file mode 100644
index 0000000..2a5194f
--- /dev/null
+++ b/docs/payroll_enhancements.md
@@ -0,0 +1,274 @@
+# 工资系统增强功能说明
+
+## 已实现的三大改进
+
+### 1. 扶养人数输入和判定 ✓
+
+#### 功能说明
+
+- **扶养家族管理**: 已有的 `dependents` 表允许录入扶养家族信息
+- **自动计算扶养人数**: 系统自动统计有效期内的扶养人数
+- **扶养判定规则表**: 新增 `dependent_rules` 表，可配置扶养条件
+
+#### API 端点
+
+- `POST /payroll/employees/{employee_id}/dependents` - 添加扶养家族
+- `GET /payroll/employees/{employee_id}/dependents` - 查看扶养家族列表
+- `GET /payroll/settings/dependent-rules` - 查看扶养判定规则
+- `POST /payroll/settings/dependent-rules` - 设置扶养判定规则
+
+#### 扶养判定条件（可配置）
+
+```
+- 所得限度額_一般: 480,000円/年
+- 所得限度額_配偶者: 480,000円/年
+- 所得限度額_配偶者特別: 1,330,000円/年
+- 年齢_特定扶養親族: 19-23歳
+- 年齢_老人扶養親族: 70歳以上
+```
+
+---
+
+### 2. 奖金计算 + 社保上限设置 ✓
+
+#### 社会保险料上限表 (`insurance_limit_settings`)
+
+可通过画面手动修改的上限值：
+
+| 设定类型                 | 2026 年初始值 | 说明                             |
+| ------------------------ | ------------- | -------------------------------- |
+| 健康保険標準報酬月額上限 | 1,390,000 円  | 健康保险计算基数上限（第 50 级） |
+| 厚生年金標準報酬月額上限 | 650,000 円    | 厚生年金计算基数上限（第 32 级） |
+| 通勤手当非課税限度額     | 150,000 円    | 通勤补贴免税上限                 |
+
+#### API 端点
+
+**社保上限管理**:
+
+- `GET /payroll/settings/insurance-limits` - 获取当前社保上限
+- `POST /payroll/settings/insurance-limits` - 创建新的上限设置
+- `PUT /payroll/settings/insurance-limits/{limit_id}` - 修改上限值
+
+**奖金计算**:
+
+- `POST /payroll/bonus/calculate` - 计算奖金
+- `GET /payroll/bonus/` - 获取奖金列表
+- `GET /payroll/bonus/{bonus_id}` - 获取奖金详情
+- `POST /payroll/bonus/{bonus_id}/approve` - 审批奖金
+
+#### 奖金计算逻辑
+
+```python
+总支给额 = 基本奖金 + 业绩奖金 + 其他奖金
+
+# 应用社保上限
+健康保险 = min(总支给额, 健康保险上限) × 健康保险率
+厚生年金 = min(总支给额, 厚生年金上限) × 厚生年金率
+介护保险 = min(总支给额, 健康保险上限) × 介护保险率 (40-64岁)
+雇用保险 = 总支给额 × 雇用保险率
+
+# 奖金所得税（特殊算法）
+所得税 = (总支给额 - 社保) × 根据前3月平均工资和扶养人数确定的税率
+
+差引支给额 = 总支给额 - 总控除额
+```
+
+#### 奖金类型
+
+- 夏季賞与（夏季奖金）
+- 冬季賞与（冬季奖金）
+- 決算賞与（结算奖金）
+- その他（其他）
+
+---
+
+### 3. 源泉徴収税額表上传功能 ✓
+
+#### 功能说明
+
+- **CSV 上传**: 可通过 API 上传源泉徴收税额表的 CSV 文件
+- **年份区分**: 每条税率记录有 `valid_from` 和 `valid_to` 字段区分年份
+- **自动应用**: 计算工资时自动使用对应年份的税额表
+
+#### API 端点
+
+- `POST /payroll/settings/income-tax/import-csv` - 上传税额表 CSV
+- `GET /payroll/settings/income-tax` - 查看当前税额表
+- `GET /payroll/settings/income-tax/calculate` - 测试税额计算
+
+#### CSV 格式示例
+
+```csv
+monthly_income_from,monthly_income_to,dependents_count,tax_amount,valid_from
+0,88000,0,0,2026-01-01
+88000,89000,0,130,2026-01-01
+89000,90000,0,200,2026-01-01
+```
+
+**字段说明**:
+
+- `monthly_income_from`: 月收入下限
+- `monthly_income_to`: 月收入上限
+- `dependents_count`: 扶养人数 (0, 1, 2, 3...)
+- `tax_amount`: 源泉徴収税额
+- `valid_from`: 适用开始日期
+
+#### 使用流程
+
+1. 准备 CSV 文件（按国税厅公布的源泉徴収税額表格式）
+2. 调用上传 API: `POST /payroll/settings/income-tax/import-csv`
+3. 系统自动应用新税额表进行计算
+
+---
+
+## 数据库变更
+
+### 新增表
+
+1. **insurance_limit_settings** - 社保上限设置表
+
+```sql
+- limit_id (主键)
+- setting_type (设定类型)
+- limit_amount (上限金额)
+- valid_from/valid_to (有效期)
+```
+
+2. **bonus_payments** - 奖金计算表
+
+```sql
+- bonus_id (主键)
+- employee_id (员工ID)
+- bonus_year/bonus_month (年月)
+- bonus_type (奖金类型)
+- base_bonus/performance_bonus/other_bonus (支给项目)
+- health_insurance/care_insurance/pension_insurance... (控除项目)
+- total_bonus/total_deduction/net_bonus (合计金额)
+```
+
+3. **dependent_rules** - 扶养判定条件表
+
+```sql
+- rule_id (主键)
+- rule_type (规则类型)
+- rule_value (规则值)
+- valid_from/valid_to (有效期)
+- description (说明)
+```
+
+### 应用数据库变更
+
+```bash
+# 1. 应用增强功能schema
+psql -U your_user -d your_database -f backend/sql/payroll_enhancements.sql
+
+# 2. 验证表是否创建成功
+psql -U your_user -d your_database -c "\dt *bonus* *insurance_limit* *dependent_rule*"
+```
+
+---
+
+## 计算逻辑改进总结
+
+### 月度工资计算
+
+1. ✅ 应用健康保险上限 (1,390,000 円)
+2. ✅ 应用厚生年金上限 (650,000 円)
+3. ✅ 应用通勤补贴免税限度 (可配置)
+4. ✅ 40-64 岁自动计算介护保险
+5. ✅ 自动统计扶养人数用于所得税计算
+
+### 奖金计算
+
+1. ✅ 应用社保上限（与工资计算一致）
+2. ✅ 特殊的奖金所得税算法
+3. ✅ 支持多种奖金类型
+4. ✅ 基于前 3 月平均工资计算税率
+
+---
+
+## 前端 TODO（建议）
+
+需要创建以下管理画面：
+
+1. **社保上限设置画面**
+
+   - 显示当前上限值
+   - 允许修改上限金额
+   - 查看历史变更记录
+
+2. **扶养判定规则画面**
+
+   - 显示当前判定条件
+   - 允许修改所得限度额
+   - 配置年龄条件
+
+3. **税额表上传画面**
+
+   - CSV 文件上传组件
+   - 预览上传内容
+   - 查看当前税额表
+
+4. **奖金计算画面**
+   - 选择员工
+   - 输入奖金金额
+   - 显示计算结果
+   - 审批流程
+
+---
+
+## API 测试示例
+
+### 1. 设置社保上限
+
+```bash
+curl -X POST http://localhost:18080/payroll/settings/insurance-limits \
+  -H "Content-Type: application/json" \
+  -d '{
+    "setting_type": "健康保険標準報酬月額上限",
+    "limit_amount": 1390000,
+    "valid_from": "2026-01-01",
+    "notes": "2026年度上限"
+  }'
+```
+
+### 2. 上传税额表 CSV
+
+```bash
+curl -X POST http://localhost:18080/payroll/settings/income-tax/import-csv \
+  -F "file=@tax_table_2026.csv" \
+  -F "valid_from=2026-01-01"
+```
+
+### 3. 计算奖金
+
+```bash
+curl -X POST http://localhost:18080/payroll/bonus/calculate \
+  -H "Content-Type: application/json" \
+  -d '{
+    "employee_id": 1,
+    "bonus_year": 2026,
+    "bonus_month": 6,
+    "bonus_type": "夏季賞与",
+    "payment_date": "2026-06-30",
+    "base_bonus": 500000,
+    "performance_bonus": 100000,
+    "calculated_by": "admin"
+  }'
+```
+
+### 4. 查询扶养判定规则
+
+```bash
+curl http://localhost:18080/payroll/settings/dependent-rules
+```
+
+---
+
+## 总结
+
+✅ **问题 1**: 扶养人数输入和判定 - 已实现，可配置判定条件  
+✅ **问题 2**: 奖金计算 + 社保上限 - 已实现，上限可手动修改  
+✅ **问题 3**: 税额表上传 - 已实现，支持 CSV 上传和年份区分
+
+所有功能都已实现 API 层，可以通过 RESTful 接口调用。下一步建议创建前端管理画面以便更方便地操作这些功能。
diff --git a/docs/payroll_quickstart.md b/docs/payroll_quickstart.md
new file mode 100644
index 0000000..3817b9e
--- /dev/null
+++ b/docs/payroll_quickstart.md
@@ -0,0 +1,171 @@
+# 給与システム - クイックスタートガイド
+
+## セットアップ手順
+
+### 1. データベーススキーマの適用
+
+```powershell
+# PostgreSQLに接続（環境に応じて認証情報を変更）
+$env:PGPASSWORD = "your_password"
+psql -U your_user -d your_database -f backend/sql/payroll_schema.sql
+```
+
+または、既存のデータベース接続を使用している場合:
+
+```powershell
+# Pythonスクリプトで実行する場合
+cd backend
+python -c "
+from app.core.database import get_connection
+with open('sql/payroll_schema.sql', 'r', encoding='utf-8') as f:
+    sql = f.read()
+with get_connection() as conn:
+    with conn.cursor() as cur:
+        cur.execute(sql)
+    conn.commit()
+print('給与システムのスキーマを適用しました')
+"
+```
+
+### 2. サーバーの起動
+
+```powershell
+cd backend
+uvicorn app.main:app --reload
+```
+
+### 3. ブラウザでアクセス
+
+http://localhost:8000/static/payroll.html
+
+## 初期データのセットアップ
+
+### 1. 保険料率の確認
+
+システムには以下の初期保険料率が登録されています（2026 年度）:
+
+- 健康保険: 10.00% (労使折半 各 5.00%)
+- 厚生年金: 18.30% (労使折半 各 9.15%)
+- 雇用保険: 1.55% (従業員 0.6% + 事業主 0.95%)
+- 労災保険: 0.30% (事業主のみ)
+
+必要に応じて「税率・保険料設定」画面で更新してください。
+
+### 2. 所得税率表のインポート
+
+サンプル CSV ファイルが `backend/income_tax_sample.csv` に用意されています。
+
+1. 「税率・保険料設定」画面を開く
+2. 「所得税率表」タブを選択
+3. 「CSV インポート」ボタンをクリック
+4. `income_tax_sample.csv` を選択
+5. 適用開始日を入力（例: 2026-01-01）
+
+### 3. 従業員の登録
+
+1. 「従業員管理」画面を開く
+2. 「新規登録」タブを選択
+3. 必要な情報を入力:
+   - 従業員コード（必須）
+   - 氏名（必須）
+   - 入社日（必須）
+   - その他の情報（任意）
+4. 「登録」ボタンをクリック
+
+### 4. 扶養家族の登録（必要な場合）
+
+1. 「従業員管理」画面で従業員を選択
+2. 従業員詳細画面の「扶養家族」セクションで追加
+
+### 5. 給与設定の登録
+
+1. 「給与設定」画面を開く
+2. 従業員を選択
+3. 「新規設定追加」ボタンをクリック
+4. 給与情報を入力:
+   - 基本給（必須）
+   - 雇用形態（必須）
+   - 支給形態（必須）
+   - 通勤手当（任意）
+   - 適用開始日（必須）
+5. 「保存」ボタンをクリック
+
+## 給与計算の実行
+
+### 月次給与計算の手順
+
+1. 「月次給与計算」画面を開く
+2. 「新規計算」ボタンをクリック
+3. 給与計算情報を入力:
+   - 従業員を選択
+   - 対象年月
+   - 支給日
+   - 勤怠情報（出勤日数、勤務時間、残業時間など）
+   - その他（住民税、その他控除など）
+4. 「計算実行」ボタンをクリック
+5. 給与明細を確認
+6. 問題なければ「承認」ボタンをクリック
+
+### 給与明細の見方
+
+**支給項目**
+
+- 基本給: 設定された基本給（欠勤がある場合は控除後）
+- 残業手当: 残業時間 × 時給 × 1.25
+- 休日手当: 休日出勤時間 × 時給 × 1.35
+- 通勤手当: 設定された通勤手当
+- その他手当: 入力されたその他手当
+- **総支給額**: 上記の合計
+
+**控除項目**
+
+- 健康保険: 総支給額 × 5.00%
+- 厚生年金: 総支給額 × 9.15%
+- 雇用保険: 総支給額 × 0.60%
+- 所得税: 所得税率表に基づいて計算
+- 住民税: 入力された金額
+- その他控除: 入力された金額
+- **総控除額**: 上記の合計
+
+**差引支給額** = 総支給額 - 総控除額
+
+## よくある質問
+
+### Q1: 給与を再計算するには？
+
+A: 給与明細画面で「再計算」ボタンをクリックしてください。ただし、承認済みの給与は再計算できません。
+
+### Q2: 承認済みの給与を修正するには？
+
+A: 承認済みの給与は変更できません。給与を削除して新規に計算し直す必要があります。
+
+### Q3: 時給制の従業員の給与計算は？
+
+A: 給与設定で「支給形態: 時給」を選択し、時給を入力してください。基本給は「時給 × 勤務時間」で自動計算されます。
+
+### Q4: 所得税が 0 円になる
+
+A: 所得税率表が登録されていない可能性があります。「税率・保険料設定」画面で所得税率表を確認してください。
+
+### Q5: 扶養家族の人数が所得税に反映されない
+
+A: 扶養家族の「有効期間」を確認してください。計算対象月に有効な扶養家族のみがカウントされます。
+
+## トラブルシューティング
+
+### エラー: 「給与設定が見つかりません」
+
+→ 「給与設定」画面で該当従業員の給与設定を登録してください
+
+### エラー: 「保険料率が見つかりません」
+
+→ 「税率・保険料設定」画面で保険料率を確認・登録してください
+
+### 所得税が正しく計算されない
+
+→ 所得税率表が正しくインポートされているか確認してください
+→ 扶養家族の有効期間が正しく設定されているか確認してください
+
+## サポート
+
+詳細なドキュメントは `docs/payroll_system.md` を参照してください。
diff --git a/docs/payroll_system.md b/docs/payroll_system.md
new file mode 100644
index 0000000..5ca0a5a
--- /dev/null
+++ b/docs/payroll_system.md
@@ -0,0 +1,221 @@
+# 給与管理システム (Payroll Management System)
+
+会計システムに統合された給与管理モジュールです。
+
+## 機能概要
+
+### 1. 従業員管理
+
+- 従業員の基本情報管理
+- 扶養家族情報の登録・管理
+- 銀行口座情報の管理
+
+### 2. 給与設定
+
+- 従業員ごとの給与基本設定
+- 基本給、時給、各種手当の設定
+- 設定履歴の管理
+
+### 3. 月次給与計算
+
+- 勤怠情報の入力
+- 給与の自動計算
+  - 基本給
+  - 残業手当（時給 × 1.25）
+  - 休日手当（時給 × 1.35）
+  - 社会保険料（健康保険、厚生年金、雇用保険）
+  - 所得税（扶養人数を考慮）
+  - 住民税
+- 給与明細の表示
+- 給与の承認機能
+
+### 4. 税率・保険料管理
+
+- 社会保険料率の管理
+  - 健康保険
+  - 厚生年金
+  - 雇用保険
+  - 労災保険
+- 所得税率表の管理
+- CSV インポート機能
+
+## セットアップ
+
+### 1. データベーススキーマの適用
+
+```bash
+# PostgreSQLに接続
+psql -U your_user -d your_database
+
+# スキーマを適用
+\i backend/sql/payroll_schema.sql
+```
+
+### 2. サーバーの起動
+
+```bash
+cd backend
+uvicorn app.main:app --reload
+```
+
+### 3. フロントエンドへのアクセス
+
+ブラウザで以下の URL にアクセス:
+
+- メインメニュー: http://localhost:8000/static/payroll.html
+- 従業員管理: http://localhost:8000/static/payroll-employees.html
+- 給与設定: http://localhost:8000/static/payroll-salary-settings.html
+- 月次給与計算: http://localhost:8000/static/payroll-calculation.html
+- 税率・保険料設定: http://localhost:8000/static/payroll-settings.html
+
+## API エンドポイント
+
+### 従業員管理
+
+- `POST /payroll/employees/` - 従業員の作成
+- `GET /payroll/employees/` - 従業員一覧の取得
+- `GET /payroll/employees/{employee_id}` - 従業員詳細の取得
+- `PUT /payroll/employees/{employee_id}` - 従業員情報の更新
+- `DELETE /payroll/employees/{employee_id}` - 従業員の削除
+
+### 扶養家族管理
+
+- `POST /payroll/employees/{employee_id}/dependents` - 扶養家族の追加
+- `GET /payroll/employees/{employee_id}/dependents` - 扶養家族一覧の取得
+- `PUT /payroll/dependents/{dependent_id}` - 扶養家族情報の更新
+- `DELETE /payroll/dependents/{dependent_id}` - 扶養家族の削除
+
+### 給与設定
+
+- `POST /payroll/settings/salary` - 給与設定の作成
+- `GET /payroll/settings/salary/{employee_id}` - 給与設定履歴の取得
+- `GET /payroll/settings/salary/{employee_id}/current` - 現在の給与設定の取得
+- `PUT /payroll/settings/salary/{setting_id}` - 給与設定の更新
+
+### 保険料率管理
+
+- `POST /payroll/settings/insurance-rates` - 保険料率の作成
+- `GET /payroll/settings/insurance-rates` - 保険料率一覧の取得
+- `GET /payroll/settings/insurance-rates/{rate_type}` - 特定保険料率の取得
+- `PUT /payroll/settings/insurance-rates/{rate_id}` - 保険料率の更新
+
+### 所得税率表管理
+
+- `POST /payroll/settings/income-tax` - 所得税率表の作成
+- `POST /payroll/settings/income-tax/import` - CSV インポート
+- `GET /payroll/settings/income-tax` - 所得税率表の取得
+- `GET /payroll/settings/income-tax/calculate` - 所得税の計算
+
+### 月次給与計算
+
+- `POST /payroll/calculation/calculate` - 給与の計算
+- `GET /payroll/calculation/` - 給与計算一覧の取得
+- `GET /payroll/calculation/{payroll_id}` - 給与明細の取得
+- `PUT /payroll/calculation/{payroll_id}` - 給与データの更新
+- `POST /payroll/calculation/{payroll_id}/recalculate` - 給与の再計算
+- `POST /payroll/calculation/{payroll_id}/approve` - 給与の承認
+- `DELETE /payroll/calculation/{payroll_id}` - 給与データの削除
+
+## 使い方
+
+### 初回セットアップフロー
+
+1. **保険料率の確認**
+
+   - 税率・保険料設定画面で、初期登録された保険料率を確認
+   - 必要に応じて更新
+
+2. **所得税率表のインポート**
+
+   - CSV ファイルを準備（フォーマット: 月収 From,月収 To,扶養人数,税額）
+   - 税率・保険料設定画面で CSV インポート
+
+3. **従業員の登録**
+
+   - 従業員管理画面で従業員を登録
+   - 必要に応じて扶養家族情報を追加
+
+4. **給与設定**
+   - 給与設定画面で各従業員の給与設定を登録
+   - 基本給、手当などを設定
+
+### 月次給与計算フロー
+
+1. **勤怠情報の入力**
+
+   - 月次給与計算画面で「新規計算」をクリック
+   - 従業員を選択
+   - 出勤日数、勤務時間、残業時間などを入力
+
+2. **給与の計算**
+
+   - 「計算実行」ボタンをクリック
+   - システムが自動的に給与を計算
+
+3. **給与明細の確認**
+
+   - 計算結果を確認
+   - 必要に応じて「再計算」
+
+4. **承認**
+   - 内容を確認後、「承認」ボタンをクリック
+   - 承認後は変更不可
+
+## データベーススキーマ
+
+### 主要テーブル
+
+1. **employees** - 従業員マスタ
+2. **dependents** - 扶養家族情報
+3. **salary_settings** - 給与基本設定
+4. **insurance_rates** - 社会保険料率マスタ
+5. **income_tax_table** - 所得税率表
+6. **monthly_payroll** - 月次給与計算ヘッダー
+7. **payroll_details** - 給与明細項目詳細
+
+## 計算ロジック
+
+### 基本給の計算
+
+- 月給制: 設定された基本給から欠勤日数を控除
+- 時給制: 時給 × 勤務時間
+
+### 残業手当
+
+- 時給 × 残業時間 × 1.25
+
+### 休日手当
+
+- 時給 × 休日出勤時間 × 1.35
+
+### 社会保険料
+
+- 健康保険: 総支給額 × 従業員負担率
+- 厚生年金: 総支給額 × 従業員負担率
+- 雇用保険: 総支給額 × 従業員負担率
+
+### 所得税
+
+1. 課税対象額 = 総支給額 - 通勤手当（非課税限度額まで） - 社会保険料
+2. 扶養家族数を取得
+3. 所得税率表から該当する税額を取得
+
+### 差引支給額
+
+- 総支給額 - 総控除額
+
+## 注意事項
+
+- 所得税率表は国税庁の「給与所得の源泉徴収税額表」に基づいて作成してください
+- 社会保険料率は年度ごとに変更される可能性があるため、定期的な更新が必要です
+- 承認済みの給与は変更・削除できません
+- 扶養家族の情報は所得税計算に影響するため、正確に入力してください
+
+## 今後の拡張機能
+
+- 賞与計算機能
+- 年末調整機能
+- 給与明細の PDF 出力
+- 銀行振込データの出力
+- 給与台帳の出力
+- 源泉徴収票の作成
diff --git a/frontend/payroll-calculation.html b/frontend/payroll-calculation.html
new file mode 100644
index 0000000..5bc8043
--- /dev/null
+++ b/frontend/payroll-calculation.html
@@ -0,0 +1,605 @@
+<!DOCTYPE html>
+<html lang="ja">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>給与管理 - 月次給与計算</title>
+    <link rel="stylesheet" href="/css/style.css" />
+    <style>
+      .filters {
+        margin-bottom: 20px;
+        padding: 15px;
+        background: #f9f9f9;
+        border-radius: 5px;
+      }
+      .filters label {
+        margin-right: 15px;
+      }
+      .payroll-list {
+        margin-top: 20px;
+      }
+      .payroll-item {
+        padding: 15px;
+        border: 1px solid #ddd;
+        margin-bottom: 10px;
+        border-radius: 5px;
+        cursor: pointer;
+      }
+      .payroll-item:hover {
+        background: #f9f9f9;
+      }
+      .status-badge {
+        padding: 4px 8px;
+        border-radius: 3px;
+        font-size: 12px;
+        font-weight: bold;
+      }
+      .status-draft {
+        background: #ffc107;
+        color: #000;
+      }
+      .status-calculated {
+        background: #17a2b8;
+        color: #fff;
+      }
+      .status-approved {
+        background: #28a745;
+        color: #fff;
+      }
+      .form-group {
+        margin-bottom: 15px;
+      }
+      .form-group label {
+        display: block;
+        margin-bottom: 5px;
+        font-weight: bold;
+      }
+      .form-group input,
+      .form-group select {
+        width: 100%;
+        padding: 8px;
+        border: 1px solid #ddd;
+        border-radius: 4px;
+      }
+      .form-row {
+        display: grid;
+        grid-template-columns: repeat(3, 1fr);
+        gap: 15px;
+      }
+      .btn {
+        padding: 10px 20px;
+        margin-right: 10px;
+        border: none;
+        border-radius: 4px;
+        cursor: pointer;
+      }
+      .btn-primary {
+        background: #007bff;
+        color: white;
+      }
+      .btn-success {
+        background: #28a745;
+        color: white;
+      }
+      .btn-secondary {
+        background: #6c757d;
+        color: white;
+      }
+      .payroll-detail {
+        margin-top: 20px;
+      }
+      .detail-section {
+        margin-bottom: 20px;
+        padding: 15px;
+        background: #f9f9f9;
+        border-radius: 5px;
+      }
+      .detail-row {
+        display: flex;
+        justify-content: space-between;
+        padding: 8px 0;
+        border-bottom: 1px solid #ddd;
+      }
+      .detail-row:last-child {
+        border-bottom: none;
+      }
+      .total-row {
+        font-weight: bold;
+        font-size: 1.2em;
+        color: #007bff;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="container">
+      <h1>給与管理 - 月次給与計算</h1>
+
+      <div class="filters">
+        <label>
+          対象年月:
+          <input
+            type="number"
+            id="filterYear"
+            style="width: 100px"
+            placeholder="年"
+          />
+        </label>
+        <label>
+          <input
+            type="number"
+            id="filterMonth"
+            style="width: 80px"
+            min="1"
+            max="12"
+            placeholder="月"
+          />
+        </label>
+        <button class="btn btn-primary" onclick="loadPayrolls()">検索</button>
+        <button class="btn btn-success" onclick="showCalculateForm()">
+          新規計算
+        </button>
+      </div>
+
+      <div id="payrollList" class="payroll-list"></div>
+
+      <!-- 給与計算フォーム（モーダル風） -->
+      <div
+        id="calculateModal"
+        style="
+          display: none;
+          position: fixed;
+          top: 50px;
+          left: 50%;
+          transform: translateX(-50%);
+          width: 800px;
+          max-height: 90vh;
+          overflow-y: auto;
+          background: white;
+          padding: 30px;
+          border: 2px solid #007bff;
+          border-radius: 10px;
+          box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
+          z-index: 1000;
+        "
+      >
+        <h2>給与計算</h2>
+        <form id="calculateForm" onsubmit="calculatePayroll(event)">
+          <div class="form-group">
+            <label>従業員 *</label>
+            <select name="employee_id" id="employeeSelect" required>
+              <option value="">選択してください</option>
+            </select>
+          </div>
+
+          <div class="form-row">
+            <div class="form-group">
+              <label>対象年 *</label>
+              <input type="number" name="payroll_year" required />
+            </div>
+            <div class="form-group">
+              <label>対象月 *</label>
+              <input
+                type="number"
+                name="payroll_month"
+                min="1"
+                max="12"
+                required
+              />
+            </div>
+            <div class="form-group">
+              <label>支給日 *</label>
+              <input type="date" name="payment_date" required />
+            </div>
+          </div>
+
+          <div class="detail-section">
+            <h3>勤怠情報</h3>
+            <div class="form-row">
+              <div class="form-group">
+                <label>出勤日数</label>
+                <input type="number" name="working_days" step="0.5" value="0" />
+              </div>
+              <div class="form-group">
+                <label>勤務時間</label>
+                <input
+                  type="number"
+                  name="working_hours"
+                  step="0.5"
+                  value="0"
+                />
+              </div>
+              <div class="form-group">
+                <label>残業時間</label>
+                <input
+                  type="number"
+                  name="overtime_hours"
+                  step="0.5"
+                  value="0"
+                />
+              </div>
+            </div>
+            <div class="form-row">
+              <div class="form-group">
+                <label>休日出勤時間</label>
+                <input
+                  type="number"
+                  name="holiday_hours"
+                  step="0.5"
+                  value="0"
+                />
+              </div>
+              <div class="form-group">
+                <label>遅刻時間</label>
+                <input type="number" name="late_hours" step="0.5" value="0" />
+              </div>
+              <div class="form-group">
+                <label>欠勤日数</label>
+                <input type="number" name="absent_days" step="0.5" value="0" />
+              </div>
+            </div>
+          </div>
+
+          <div class="detail-section">
+            <h3>その他</h3>
+            <div class="form-row">
+              <div class="form-group">
+                <label>その他手当</label>
+                <input
+                  type="number"
+                  name="other_allowance"
+                  step="0.01"
+                  value="0"
+                />
+              </div>
+              <div class="form-group">
+                <label>住民税</label>
+                <input
+                  type="number"
+                  name="resident_tax"
+                  step="0.01"
+                  value="0"
+                />
+              </div>
+              <div class="form-group">
+                <label>その他控除</label>
+                <input
+                  type="number"
+                  name="other_deduction"
+                  step="0.01"
+                  value="0"
+                />
+              </div>
+            </div>
+          </div>
+
+          <button type="submit" class="btn btn-primary">計算実行</button>
+          <button
+            type="button"
+            class="btn btn-secondary"
+            onclick="closeCalculateForm()"
+          >
+            キャンセル
+          </button>
+        </form>
+      </div>
+
+      <!-- 給与明細表示 -->
+      <div
+        id="payrollDetail"
+        class="payroll-detail"
+        style="display: none"
+      ></div>
+    </div>
+
+    <script>
+      const API_BASE = "http://localhost:8000";
+
+      async function loadEmployees() {
+        const response = await fetch(
+          `${API_BASE}/payroll/employees/?is_active=true`
+        );
+        const employees = await response.json();
+
+        const select = document.getElementById("employeeSelect");
+        select.innerHTML =
+          '<option value="">選択してください</option>' +
+          employees
+            .map(
+              (emp) =>
+                `<option value="${emp.employee_id}">${emp.employee_code} - ${emp.name}</option>`
+            )
+            .join("");
+      }
+
+      async function loadPayrolls() {
+        const year = document.getElementById("filterYear").value;
+        const month = document.getElementById("filterMonth").value;
+
+        const params = new URLSearchParams();
+        if (year) params.append("payroll_year", year);
+        if (month) params.append("payroll_month", month);
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/calculation/?${params}`
+          );
+          const payrolls = await response.json();
+
+          const html = payrolls
+            .map(
+              (p) => `
+                    <div class="payroll-item" onclick="viewPayroll(${
+                      p.payroll_id
+                    })">
+                        <div>
+                            <strong>${p.payroll_year}年${
+                p.payroll_month
+              }月</strong>
+                            <span class="status-badge status-${
+                              p.status
+                            }">${getStatusLabel(p.status)}</span>
+                        </div>
+                        <div>
+                            従業員ID: ${p.employee_id} | 支給日: ${
+                p.payment_date
+              }
+                        </div>
+                        <div>
+                            <strong>差引支給額: ¥${Number(
+                              p.net_payment
+                            ).toLocaleString()}</strong>
+                            (総支給: ¥${Number(
+                              p.total_payment
+                            ).toLocaleString()} - 控除: ¥${Number(
+                p.total_deduction
+              ).toLocaleString()})
+                        </div>
+                    </div>
+                `
+            )
+            .join("");
+
+          document.getElementById("payrollList").innerHTML =
+            html || "<p>給与データがありません</p>";
+        } catch (error) {
+          alert("給与一覧の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      function getStatusLabel(status) {
+        const labels = {
+          draft: "下書き",
+          calculated: "計算済み",
+          approved: "承認済み",
+          paid: "支払済み",
+        };
+        return labels[status] || status;
+      }
+
+      function showCalculateForm() {
+        document.getElementById("calculateModal").style.display = "block";
+        loadEmployees();
+
+        // デフォルト値設定
+        const now = new Date();
+        document.querySelector('[name="payroll_year"]').value =
+          now.getFullYear();
+        document.querySelector('[name="payroll_month"]').value =
+          now.getMonth() + 1;
+      }
+
+      function closeCalculateForm() {
+        document.getElementById("calculateModal").style.display = "none";
+        document.getElementById("calculateForm").reset();
+      }
+
+      async function calculatePayroll(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = {};
+
+        formData.forEach((value, key) => {
+          data[key] = isNaN(value) || value === "" ? value : Number(value);
+        });
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/calculation/calculate`,
+            {
+              method: "POST",
+              headers: { "Content-Type": "application/json" },
+              body: JSON.stringify(data),
+            }
+          );
+
+          if (response.ok) {
+            const result = await response.json();
+            alert("給与計算が完了しました");
+            closeCalculateForm();
+            viewPayroll(result.payroll_id);
+          } else {
+            const error = await response.json();
+            alert("計算に失敗しました: " + error.detail);
+          }
+        } catch (error) {
+          alert("計算に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function viewPayroll(payrollId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/calculation/${payrollId}`
+          );
+          const payroll = await response.json();
+
+          const html = `
+                    <h2>${payroll.payroll_year}年${
+            payroll.payroll_month
+          }月 給与明細</h2>
+                    <p>従業員ID: ${payroll.employee_id} | 支給日: ${
+            payroll.payment_date
+          }</p>
+                    <p>ステータス: <span class="status-badge status-${
+                      payroll.status
+                    }">${getStatusLabel(payroll.status)}</span></p>
+
+                    <div class="detail-section">
+                        <h3>勤怠情報</h3>
+                        <div class="detail-row"><span>出勤日数:</span><span>${
+                          payroll.working_days
+                        }日</span></div>
+                        <div class="detail-row"><span>勤務時間:</span><span>${
+                          payroll.working_hours
+                        }時間</span></div>
+                        <div class="detail-row"><span>残業時間:</span><span>${
+                          payroll.overtime_hours
+                        }時間</span></div>
+                        <div class="detail-row"><span>休日出勤:</span><span>${
+                          payroll.holiday_hours
+                        }時間</span></div>
+                        <div class="detail-row"><span>欠勤日数:</span><span>${
+                          payroll.absent_days
+                        }日</span></div>
+                    </div>
+
+                    <div class="detail-section">
+                        <h3>支給項目</h3>
+                        <div class="detail-row"><span>基本給:</span><span>¥${Number(
+                          payroll.base_salary
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>残業手当:</span><span>¥${Number(
+                          payroll.overtime_pay
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>休日手当:</span><span>¥${Number(
+                          payroll.holiday_pay
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>通勤手当:</span><span>¥${Number(
+                          payroll.commute_allowance
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>その他手当:</span><span>¥${Number(
+                          payroll.other_allowance
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row total-row"><span>総支給額:</span><span>¥${Number(
+                          payroll.total_payment
+                        ).toLocaleString()}</span></div>
+                    </div>
+
+                    <div class="detail-section">
+                        <h3>控除項目</h3>
+                        <div class="detail-row"><span>健康保険:</span><span>¥${Number(
+                          payroll.health_insurance
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>厚生年金:</span><span>¥${Number(
+                          payroll.pension_insurance
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>雇用保険:</span><span>¥${Number(
+                          payroll.employment_insurance
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>所得税:</span><span>¥${Number(
+                          payroll.income_tax
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>住民税:</span><span>¥${Number(
+                          payroll.resident_tax
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row"><span>その他控除:</span><span>¥${Number(
+                          payroll.other_deduction
+                        ).toLocaleString()}</span></div>
+                        <div class="detail-row total-row"><span>総控除額:</span><span>¥${Number(
+                          payroll.total_deduction
+                        ).toLocaleString()}</span></div>
+                    </div>
+
+                    <div class="detail-section" style="background:#e7f3ff;">
+                        <div class="detail-row total-row" style="font-size:1.5em;">
+                            <span>差引支給額:</span>
+                            <span>¥${Number(
+                              payroll.net_payment
+                            ).toLocaleString()}</span>
+                        </div>
+                    </div>
+
+                    ${
+                      payroll.status === "calculated"
+                        ? `
+                        <button class="btn btn-success" onclick="approvePayroll(${payroll.payroll_id})">承認</button>
+                        <button class="btn btn-primary" onclick="recalculatePayroll(${payroll.payroll_id})">再計算</button>
+                    `
+                        : ""
+                    }
+                    <button class="btn btn-secondary" onclick="document.getElementById('payrollDetail').style.display='none'">閉じる</button>
+                `;
+
+          document.getElementById("payrollDetail").innerHTML = html;
+          document.getElementById("payrollDetail").style.display = "block";
+          document
+            .getElementById("payrollDetail")
+            .scrollIntoView({ behavior: "smooth" });
+        } catch (error) {
+          alert("給与明細の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function approvePayroll(payrollId) {
+        if (!confirm("この給与を承認しますか?")) return;
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/calculation/${payrollId}/approve`,
+            {
+              method: "POST",
+              headers: { "Content-Type": "application/json" },
+              body: JSON.stringify({ approved_by: "admin" }),
+            }
+          );
+
+          if (response.ok) {
+            alert("承認しました");
+            viewPayroll(payrollId);
+            loadPayrolls();
+          } else {
+            const error = await response.json();
+            alert("承認に失敗しました: " + error.detail);
+          }
+        } catch (error) {
+          alert("承認に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function recalculatePayroll(payrollId) {
+        if (!confirm("給与を再計算しますか?")) return;
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/calculation/${payrollId}/recalculate`,
+            {
+              method: "POST",
+            }
+          );
+
+          if (response.ok) {
+            alert("再計算が完了しました");
+            viewPayroll(payrollId);
+          } else {
+            const error = await response.json();
+            alert("再計算に失敗しました: " + error.detail);
+          }
+        } catch (error) {
+          alert("再計算に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // 初期化
+      const now = new Date();
+      document.getElementById("filterYear").value = now.getFullYear();
+      document.getElementById("filterMonth").value = now.getMonth() + 1;
+      loadPayrolls();
+    </script>
+  </body>
+</html>
diff --git a/frontend/payroll-employees.html b/frontend/payroll-employees.html
new file mode 100644
index 0000000..d338cb7
--- /dev/null
+++ b/frontend/payroll-employees.html
@@ -0,0 +1,371 @@
+<!DOCTYPE html>
+<html lang="ja">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>給与管理 - 従業員管理</title>
+    <link rel="stylesheet" href="/css/style.css" />
+    <style>
+      .nav-tabs {
+        display: flex;
+        gap: 10px;
+        margin-bottom: 20px;
+        border-bottom: 2px solid #ddd;
+      }
+      .nav-tab {
+        padding: 10px 20px;
+        cursor: pointer;
+        border: none;
+        background: #f0f0f0;
+        border-radius: 5px 5px 0 0;
+      }
+      .nav-tab.active {
+        background: #007bff;
+        color: white;
+      }
+      .tab-content {
+        display: none;
+      }
+      .tab-content.active {
+        display: block;
+      }
+      .employee-list {
+        margin-top: 20px;
+      }
+      .employee-item {
+        padding: 15px;
+        border: 1px solid #ddd;
+        margin-bottom: 10px;
+        border-radius: 5px;
+        cursor: pointer;
+      }
+      .employee-item:hover {
+        background: #f9f9f9;
+      }
+      .form-group {
+        margin-bottom: 15px;
+      }
+      .form-group label {
+        display: block;
+        margin-bottom: 5px;
+        font-weight: bold;
+      }
+      .form-group input,
+      .form-group select,
+      .form-group textarea {
+        width: 100%;
+        padding: 8px;
+        border: 1px solid #ddd;
+        border-radius: 4px;
+      }
+      .btn {
+        padding: 10px 20px;
+        margin-right: 10px;
+        border: none;
+        border-radius: 4px;
+        cursor: pointer;
+      }
+      .btn-primary {
+        background: #007bff;
+        color: white;
+      }
+      .btn-secondary {
+        background: #6c757d;
+        color: white;
+      }
+      .btn-danger {
+        background: #dc3545;
+        color: white;
+      }
+      .dependent-list {
+        margin-top: 20px;
+        padding: 15px;
+        background: #f9f9f9;
+        border-radius: 5px;
+      }
+      .dependent-item {
+        padding: 10px;
+        border: 1px solid #ddd;
+        margin-bottom: 10px;
+        background: white;
+        border-radius: 4px;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="container">
+      <h1>給与管理 - 従業員管理</h1>
+
+      <div class="nav-tabs">
+        <button class="nav-tab active" onclick="showTab('list')">
+          従業員一覧
+        </button>
+        <button class="nav-tab" onclick="showTab('create')">新規登録</button>
+        <button
+          class="nav-tab"
+          onclick="showTab('detail')"
+          id="detailTab"
+          style="display: none"
+        >
+          従業員詳細
+        </button>
+      </div>
+
+      <!-- 従業員一覧タブ -->
+      <div id="tab-list" class="tab-content active">
+        <div class="filters">
+          <label>
+            <input
+              type="checkbox"
+              id="filterActive"
+              checked
+              onchange="loadEmployees()"
+            />
+            在職中のみ表示
+          </label>
+        </div>
+        <div id="employeeList" class="employee-list"></div>
+      </div>
+
+      <!-- 新規登録タブ -->
+      <div id="tab-create" class="tab-content">
+        <h2>従業員の新規登録</h2>
+        <form id="createForm" onsubmit="createEmployee(event)">
+          <div class="form-group">
+            <label>従業員コード *</label>
+            <input type="text" name="employee_code" required />
+          </div>
+          <div class="form-group">
+            <label>氏名 *</label>
+            <input type="text" name="name" required />
+          </div>
+          <div class="form-group">
+            <label>フリガナ</label>
+            <input type="text" name="name_kana" />
+          </div>
+          <div class="form-group">
+            <label>メールアドレス</label>
+            <input type="email" name="email" />
+          </div>
+          <div class="form-group">
+            <label>電話番号</label>
+            <input type="tel" name="phone" />
+          </div>
+          <div class="form-group">
+            <label>入社日 *</label>
+            <input type="date" name="hire_date" required />
+          </div>
+          <div class="form-group">
+            <label>銀行名</label>
+            <input type="text" name="bank_name" />
+          </div>
+          <div class="form-group">
+            <label>支店名</label>
+            <input type="text" name="bank_branch" />
+          </div>
+          <div class="form-group">
+            <label>口座番号</label>
+            <input type="text" name="bank_account_number" />
+          </div>
+          <div class="form-group">
+            <label>口座種別</label>
+            <select name="bank_account_type">
+              <option value="">選択してください</option>
+              <option value="普通">普通</option>
+              <option value="当座">当座</option>
+            </select>
+          </div>
+          <div class="form-group">
+            <label>備考</label>
+            <textarea name="notes" rows="3"></textarea>
+          </div>
+          <button type="submit" class="btn btn-primary">登録</button>
+          <button
+            type="button"
+            class="btn btn-secondary"
+            onclick="showTab('list')"
+          >
+            キャンセル
+          </button>
+        </form>
+      </div>
+
+      <!-- 従業員詳細タブ -->
+      <div id="tab-detail" class="tab-content">
+        <div id="employeeDetail"></div>
+      </div>
+    </div>
+
+    <script>
+      const API_BASE = "http://localhost:8000";
+      let currentEmployee = null;
+
+      function showTab(tabName) {
+        document
+          .querySelectorAll(".nav-tab")
+          .forEach((tab) => tab.classList.remove("active"));
+        document
+          .querySelectorAll(".tab-content")
+          .forEach((content) => content.classList.remove("active"));
+
+        if (tabName === "list") {
+          document.querySelector(".nav-tab").classList.add("active");
+          document.getElementById("tab-list").classList.add("active");
+          loadEmployees();
+        } else if (tabName === "create") {
+          document.querySelectorAll(".nav-tab")[1].classList.add("active");
+          document.getElementById("tab-create").classList.add("active");
+        } else if (tabName === "detail") {
+          document.getElementById("detailTab").classList.add("active");
+          document.getElementById("tab-detail").classList.add("active");
+        }
+      }
+
+      async function loadEmployees() {
+        const isActive = document.getElementById("filterActive").checked;
+        const url = `${API_BASE}/payroll/employees/${
+          isActive ? "?is_active=true" : ""
+        }`;
+
+        try {
+          const response = await fetch(url);
+          const employees = await response.json();
+
+          const html = employees
+            .map(
+              (emp) => `
+                    <div class="employee-item" onclick="viewEmployee(${
+                      emp.employee_id
+                    })">
+                        <strong>${emp.employee_code}</strong> - ${emp.name}
+                        ${emp.name_kana ? `(${emp.name_kana})` : ""}
+                        <br>
+                        <small>入社日: ${emp.hire_date} ${
+                emp.termination_date ? ` | 退職日: ${emp.termination_date}` : ""
+              }</small>
+                    </div>
+                `
+            )
+            .join("");
+
+          document.getElementById("employeeList").innerHTML =
+            html || "<p>従業員が登録されていません</p>";
+        } catch (error) {
+          alert("従業員一覧の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function createEmployee(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = Object.fromEntries(formData.entries());
+
+        // 空の値を除外
+        Object.keys(data).forEach((key) => {
+          if (data[key] === "") {
+            delete data[key];
+          }
+        });
+
+        try {
+          const response = await fetch(`${API_BASE}/payroll/employees/`, {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(data),
+          });
+
+          if (response.ok) {
+            alert("従業員を登録しました");
+            form.reset();
+            showTab("list");
+          } else {
+            const error = await response.json();
+            alert("登録に失敗しました: " + error.detail);
+          }
+        } catch (error) {
+          alert("登録に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function viewEmployee(employeeId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/employees/${employeeId}`
+          );
+          const employee = await response.json();
+          currentEmployee = employee;
+
+          const html = `
+                    <h2>${employee.name} (${employee.employee_code})</h2>
+                    <p><strong>フリガナ:</strong> ${
+                      employee.name_kana || "-"
+                    }</p>
+                    <p><strong>メール:</strong> ${employee.email || "-"}</p>
+                    <p><strong>電話:</strong> ${employee.phone || "-"}</p>
+                    <p><strong>入社日:</strong> ${employee.hire_date}</p>
+                    <p><strong>退職日:</strong> ${
+                      employee.termination_date || "-"
+                    }</p>
+                    <p><strong>銀行:</strong> ${employee.bank_name || "-"} ${
+            employee.bank_branch || ""
+          }</p>
+                    <p><strong>口座:</strong> ${
+                      employee.bank_account_type || ""
+                    } ${employee.bank_account_number || "-"}</p>
+                    <p><strong>備考:</strong> ${employee.notes || "-"}</p>
+
+                    <div class="dependent-list">
+                        <h3>扶養家族</h3>
+                        ${
+                          employee.dependents
+                            .map(
+                              (dep) => `
+                            <div class="dependent-item">
+                                <strong>${dep.name}</strong> (${
+                                dep.relationship
+                              })
+                                ${
+                                  dep.birth_date
+                                    ? ` - 生年月日: ${dep.birth_date}`
+                                    : ""
+                                }
+                                ${
+                                  dep.is_spouse
+                                    ? ' <span style="color:blue;">[配偶者]</span>'
+                                    : ""
+                                }
+                                ${
+                                  dep.is_disabled
+                                    ? ' <span style="color:red;">[障害者]</span>'
+                                    : ""
+                                }
+                                <br><small>有効期間: ${dep.valid_from} ～ ${
+                                dep.valid_to || "現在"
+                              }</small>
+                            </div>
+                        `
+                            )
+                            .join("") || "<p>扶養家族が登録されていません</p>"
+                        }
+                    </div>
+
+                    <button class="btn btn-secondary" onclick="showTab('list')">戻る</button>
+                `;
+
+          document.getElementById("employeeDetail").innerHTML = html;
+          document.getElementById("detailTab").style.display = "block";
+          showTab("detail");
+        } catch (error) {
+          alert("従業員情報の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // 初期化
+      loadEmployees();
+    </script>
+  </body>
+</html>
diff --git a/frontend/payroll-salary-settings.html b/frontend/payroll-salary-settings.html
new file mode 100644
index 0000000..8305d7f
--- /dev/null
+++ b/frontend/payroll-salary-settings.html
@@ -0,0 +1,378 @@
+<!DOCTYPE html>
+<html lang="ja">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>給与管理 - 給与設定</title>
+    <link rel="stylesheet" href="/css/style.css" />
+    <style>
+      .employee-select {
+        margin-bottom: 20px;
+        padding: 15px;
+        background: #f9f9f9;
+        border-radius: 5px;
+      }
+      .form-group {
+        margin-bottom: 15px;
+      }
+      .form-group label {
+        display: block;
+        margin-bottom: 5px;
+        font-weight: bold;
+      }
+      .form-group input,
+      .form-group select {
+        width: 100%;
+        padding: 8px;
+        border: 1px solid #ddd;
+        border-radius: 4px;
+      }
+      .btn {
+        padding: 10px 20px;
+        margin-right: 10px;
+        border: none;
+        border-radius: 4px;
+        cursor: pointer;
+      }
+      .btn-primary {
+        background: #007bff;
+        color: white;
+      }
+      .btn-secondary {
+        background: #6c757d;
+        color: white;
+      }
+      table {
+        width: 100%;
+        border-collapse: collapse;
+        margin-top: 20px;
+      }
+      table th,
+      table td {
+        border: 1px solid #ddd;
+        padding: 10px;
+        text-align: left;
+      }
+      table th {
+        background: #f0f0f0;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="container">
+      <h1>給与管理 - 給与設定</h1>
+
+      <div class="employee-select">
+        <label><strong>従業員を選択:</strong></label>
+        <select id="employeeSelect" onchange="loadSalarySettings()">
+          <option value="">従業員を選択してください</option>
+        </select>
+      </div>
+
+      <div id="settingsContent" style="display: none">
+        <h2>給与設定履歴</h2>
+        <button class="btn btn-primary" onclick="showAddForm()">
+          新規設定追加
+        </button>
+        <div id="settingsList"></div>
+
+        <div
+          id="addForm"
+          style="
+            display: none;
+            margin-top: 20px;
+            padding: 20px;
+            border: 2px solid #007bff;
+            border-radius: 5px;
+          "
+        >
+          <h3>給与設定の追加</h3>
+          <form onsubmit="saveSalarySetting(event)">
+            <div class="form-group">
+              <label>基本給 (円) *</label>
+              <input type="number" name="base_salary" step="0.01" required />
+            </div>
+            <div class="form-group">
+              <label>時給 (円)</label>
+              <input type="number" name="hourly_rate" step="0.01" />
+              <small>時給制の場合に入力してください</small>
+            </div>
+            <div class="form-group">
+              <label>雇用形態 *</label>
+              <select name="employment_type" required>
+                <option value="">選択してください</option>
+                <option value="正社員">正社員</option>
+                <option value="契約社員">契約社員</option>
+                <option value="パート">パート</option>
+                <option value="アルバイト">アルバイト</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label>支給形態 *</label>
+              <select name="payment_type" required>
+                <option value="">選択してください</option>
+                <option value="月給">月給</option>
+                <option value="時給">時給</option>
+                <option value="日給">日給</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label>通勤手当 (円)</label>
+              <input
+                type="number"
+                name="commute_allowance"
+                step="0.01"
+                value="0"
+              />
+            </div>
+            <div class="form-group">
+              <label>その他手当 (円)</label>
+              <input
+                type="number"
+                name="other_allowance"
+                step="0.01"
+                value="0"
+              />
+            </div>
+            <div class="form-group">
+              <label>適用開始日 *</label>
+              <input type="date" name="valid_from" required />
+            </div>
+            <div class="form-group">
+              <label>適用終了日</label>
+              <input type="date" name="valid_to" />
+              <small>通常は空欄のままにしてください</small>
+            </div>
+            <button type="submit" class="btn btn-primary">保存</button>
+            <button
+              type="button"
+              class="btn btn-secondary"
+              onclick="hideAddForm()"
+            >
+              キャンセル
+            </button>
+          </form>
+        </div>
+
+        <div
+          id="currentSetting"
+          style="
+            margin-top: 30px;
+            padding: 20px;
+            background: #e7f3ff;
+            border-radius: 5px;
+          "
+        >
+          <h3>現在の給与設定</h3>
+          <div id="currentSettingContent"></div>
+        </div>
+      </div>
+    </div>
+
+    <script>
+      const API_BASE = "http://localhost:8000";
+      let currentEmployeeId = null;
+
+      async function loadEmployees() {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/employees/?is_active=true`
+          );
+          const employees = await response.json();
+
+          const select = document.getElementById("employeeSelect");
+          select.innerHTML =
+            '<option value="">従業員を選択してください</option>' +
+            employees
+              .map(
+                (emp) =>
+                  `<option value="${emp.employee_id}">${emp.employee_code} - ${emp.name}</option>`
+              )
+              .join("");
+        } catch (error) {
+          alert("従業員一覧の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function loadSalarySettings() {
+        const employeeId = document.getElementById("employeeSelect").value;
+        if (!employeeId) {
+          document.getElementById("settingsContent").style.display = "none";
+          return;
+        }
+
+        currentEmployeeId = employeeId;
+        document.getElementById("settingsContent").style.display = "block";
+
+        try {
+          // 給与設定履歴を取得
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/salary/${employeeId}`
+          );
+          const settings = await response.json();
+
+          const html = `
+                    <table>
+                        <thead>
+                            <tr>
+                                <th>適用期間</th>
+                                <th>基本給</th>
+                                <th>時給</th>
+                                <th>雇用形態</th>
+                                <th>支給形態</th>
+                                <th>通勤手当</th>
+                                <th>その他手当</th>
+                            </tr>
+                        </thead>
+                        <tbody>
+                            ${settings
+                              .map(
+                                (s) => `
+                                <tr>
+                                    <td>${s.valid_from} ～ ${
+                                  s.valid_to || "現在"
+                                }</td>
+                                    <td>¥${Number(
+                                      s.base_salary
+                                    ).toLocaleString()}</td>
+                                    <td>${
+                                      s.hourly_rate
+                                        ? "¥" +
+                                          Number(s.hourly_rate).toLocaleString()
+                                        : "-"
+                                    }</td>
+                                    <td>${s.employment_type}</td>
+                                    <td>${s.payment_type}</td>
+                                    <td>¥${Number(
+                                      s.commute_allowance
+                                    ).toLocaleString()}</td>
+                                    <td>¥${Number(
+                                      s.other_allowance
+                                    ).toLocaleString()}</td>
+                                </tr>
+                            `
+                              )
+                              .join("")}
+                        </tbody>
+                    </table>
+                `;
+
+          document.getElementById("settingsList").innerHTML = html;
+
+          // 現在の設定を取得
+          loadCurrentSetting(employeeId);
+        } catch (error) {
+          alert("給与設定の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function loadCurrentSetting(employeeId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/salary/${employeeId}/current`
+          );
+          if (response.ok) {
+            const setting = await response.json();
+
+            const html = `
+                        <div style="display:grid; grid-template-columns: repeat(2, 1fr); gap:15px;">
+                            <div><strong>基本給:</strong> ¥${Number(
+                              setting.base_salary
+                            ).toLocaleString()}</div>
+                            <div><strong>時給:</strong> ${
+                              setting.hourly_rate
+                                ? "¥" +
+                                  Number(setting.hourly_rate).toLocaleString()
+                                : "-"
+                            }</div>
+                            <div><strong>雇用形態:</strong> ${
+                              setting.employment_type
+                            }</div>
+                            <div><strong>支給形態:</strong> ${
+                              setting.payment_type
+                            }</div>
+                            <div><strong>通勤手当:</strong> ¥${Number(
+                              setting.commute_allowance
+                            ).toLocaleString()}</div>
+                            <div><strong>その他手当:</strong> ¥${Number(
+                              setting.other_allowance
+                            ).toLocaleString()}</div>
+                            <div><strong>適用期間:</strong> ${
+                              setting.valid_from
+                            } ～ ${setting.valid_to || "現在"}</div>
+                        </div>
+                    `;
+
+            document.getElementById("currentSettingContent").innerHTML = html;
+          } else {
+            document.getElementById("currentSettingContent").innerHTML =
+              "<p>給与設定が登録されていません</p>";
+          }
+        } catch (error) {
+          document.getElementById("currentSettingContent").innerHTML =
+            "<p>給与設定の取得に失敗しました</p>";
+        }
+      }
+
+      function showAddForm() {
+        document.getElementById("addForm").style.display = "block";
+        // デフォルト値設定
+        document.querySelector('[name="valid_from"]').value = new Date()
+          .toISOString()
+          .split("T")[0];
+      }
+
+      function hideAddForm() {
+        document.getElementById("addForm").style.display = "none";
+        document.querySelector("#addForm form").reset();
+      }
+
+      async function saveSalarySetting(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = Object.fromEntries(formData.entries());
+
+        data.employee_id = parseInt(currentEmployeeId);
+        data.base_salary = parseFloat(data.base_salary) || 0;
+        data.commute_allowance = parseFloat(data.commute_allowance) || 0;
+        data.other_allowance = parseFloat(data.other_allowance) || 0;
+
+        if (data.hourly_rate) {
+          data.hourly_rate = parseFloat(data.hourly_rate);
+        } else {
+          delete data.hourly_rate;
+        }
+
+        if (!data.valid_to) {
+          delete data.valid_to;
+        }
+
+        try {
+          const response = await fetch(`${API_BASE}/payroll/settings/salary`, {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(data),
+          });
+
+          if (response.ok) {
+            alert("給与設定を保存しました");
+            hideAddForm();
+            loadSalarySettings();
+          } else {
+            const error = await response.json();
+            alert("保存に失敗しました: " + error.detail);
+          }
+        } catch (error) {
+          alert("保存に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // 初期化
+      loadEmployees();
+    </script>
+  </body>
+</html>
diff --git a/frontend/payroll-settings.html b/frontend/payroll-settings.html
new file mode 100644
index 0000000..f42e281
--- /dev/null
+++ b/frontend/payroll-settings.html
@@ -0,0 +1,1298 @@
+<!DOCTYPE html>
+<html lang="ja">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>給与管理 - 設定</title>
+    <link rel="stylesheet" href="/css/style.css" />
+    <style>
+      .nav-tabs {
+        display: flex;
+        gap: 10px;
+        margin-bottom: 20px;
+        border-bottom: 2px solid #ddd;
+        flex-wrap: wrap;
+      }
+      .nav-tab {
+        padding: 10px 20px;
+        cursor: pointer;
+        border: none;
+        background: #f0f0f0;
+        border-radius: 5px 5px 0 0;
+      }
+      .nav-tab.active {
+        background: #007bff;
+        color: white;
+      }
+      .tab-content {
+        display: none;
+      }
+      .tab-content.active {
+        display: block;
+      }
+      .form-group {
+        margin-bottom: 15px;
+      }
+      .form-group label {
+        display: block;
+        margin-bottom: 5px;
+        font-weight: bold;
+      }
+      .form-group input,
+      .form-group select,
+      .form-group textarea {
+        width: 100%;
+        padding: 8px;
+        border: 1px solid #ddd;
+        border-radius: 4px;
+        box-sizing: border-box;
+      }
+      .form-row {
+        display: grid;
+        grid-template-columns: 1fr 1fr;
+        gap: 15px;
+      }
+      .form-row-3 {
+        display: grid;
+        grid-template-columns: 1fr 1fr 1fr;
+        gap: 15px;
+      }
+      .btn {
+        padding: 10px 20px;
+        margin-right: 10px;
+        border: none;
+        border-radius: 4px;
+        cursor: pointer;
+      }
+      .btn-primary {
+        background: #007bff;
+        color: white;
+      }
+      .btn-secondary {
+        background: #6c757d;
+        color: white;
+      }
+      .btn-danger {
+        background: #dc3545;
+        color: white;
+      }
+      .btn-small {
+        padding: 5px 10px;
+        font-size: 12px;
+      }
+      table {
+        width: 100%;
+        border-collapse: collapse;
+        margin-top: 20px;
+      }
+      table th,
+      table td {
+        border: 1px solid #ddd;
+        padding: 10px;
+        text-align: left;
+      }
+      table th {
+        background: #f0f0f0;
+      }
+      .filter-section {
+        background: #f9f9f9;
+        padding: 15px;
+        border-radius: 5px;
+        margin-bottom: 20px;
+      }
+      .modal-form {
+        display: none;
+        margin-top: 20px;
+        padding: 20px;
+        border: 2px solid #007bff;
+        border-radius: 5px;
+        background: white;
+      }
+      .info-box {
+        background: #e7f3ff;
+        padding: 15px;
+        border-left: 4px solid #007bff;
+        margin-bottom: 20px;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="container">
+      <h1>給与管理 - 設定</h1>
+
+      <div class="nav-tabs">
+        <button class="nav-tab active" onclick="showTab('insurance')">
+          保険料率
+        </button>
+        <button class="nav-tab" onclick="showTab('child-support')">
+          子ども・子育て拠出金
+        </button>
+        <button class="nav-tab" onclick="showTab('limits')">上限設定</button>
+        <button class="nav-tab" onclick="showTab('tax')">所得税率表</button>
+      </div>
+
+      <!-- 保険料率タブ -->
+      <div id="tab-insurance" class="tab-content active">
+        <h2>社会保険料率設定</h2>
+
+        <div class="info-box">
+          <strong>設定のポイント:</strong>
+          <ul style="margin: 10px 0 0 20px">
+            <li>年度ごとに設定します（複数の料率を入力可能）</li>
+            <li>給与計算と賞与計算で異なる料率を設定できます</li>
+            <li>事業所所在地（都道府県）ごとに設定できます</li>
+            <li>介護保険の適用年齢は設定可能です（デフォルト: 40歳以上）</li>
+          </ul>
+        </div>
+
+        <!-- フィルター -->
+        <div class="filter-section">
+          <div class="form-row-3">
+            <div class="form-group" style="margin-bottom: 0">
+              <label>年度</label>
+              <input
+                type="number"
+                id="filterInsuranceYear"
+                onchange="loadInsuranceRates()"
+                placeholder="全て"
+                min="2020"
+                max="2050"
+                style="width: 100%"
+              />
+              <small style="color: #666">※空欄で全て表示</small>
+            </div>
+            <div class="form-group" style="margin-bottom: 0">
+              <label>計算対象</label>
+              <select
+                id="filterCalculationTarget"
+                onchange="loadInsuranceRates()"
+              >
+                <option value="">全て</option>
+                <option value="給与">給与</option>
+                <option value="賞与">賞与</option>
+              </select>
+            </div>
+            <div class="form-group" style="margin-bottom: 0">
+              <label>都道府県</label>
+              <select id="filterPrefecture" onchange="loadInsuranceRates()">
+                <option value="">全て</option>
+                <option value="東京都">東京都</option>
+                <option value="神奈川県">神奈川県</option>
+                <option value="千葉県">千葉県</option>
+                <option value="埼玉県">埼玉県</option>
+              </select>
+            </div>
+          </div>
+        </div>
+
+        <button class="btn btn-primary" onclick="showInsuranceForm()">
+          新規追加
+        </button>
+        <div id="insuranceList"></div>
+
+        <div id="insuranceForm" class="modal-form">
+          <h3 id="insuranceFormTitle">保険料率の登録</h3>
+          <form id="insuranceRateForm" onsubmit="saveInsuranceRate(event)">
+            <input type="hidden" name="rate_id" id="editRateId" />
+            <input type="hidden" name="edit_mode" id="editMode" value="false" />
+            <div class="form-row">
+              <div class="form-group">
+                <label>年度 *</label>
+                <input
+                  type="number"
+                  name="rate_year"
+                  min="2020"
+                  max="2050"
+                  required
+                  placeholder="例: 2026"
+                />
+              </div>
+              <div class="form-group">
+                <label>計算対象 *</label>
+                <select name="calculation_target" required>
+                  <option value="">選択してください</option>
+                  <option value="給与">給与</option>
+                  <option value="賞与">賞与</option>
+                </select>
+              </div>
+            </div>
+
+            <div class="form-row">
+              <div class="form-group">
+                <label>保険種類 *</label>
+                <select name="rate_type" required>
+                  <option value="">選択してください</option>
+                  <option value="健康保険">健康保険</option>
+                  <option value="介護保険">介護保険</option>
+                  <option value="厚生年金">厚生年金</option>
+                  <option value="雇用保険">雇用保険</option>
+                  <option value="労災保険">労災保険</option>
+                </select>
+              </div>
+              <div class="form-group">
+                <label>事業所所在地 *</label>
+                <select name="prefecture" required>
+                  <option value="東京都">東京都</option>
+                  <option value="神奈川県">神奈川県</option>
+                  <option value="千葉県">千葉県</option>
+                  <option value="埼玉県">埼玉県</option>
+                </select>
+              </div>
+            </div>
+
+            <div class="form-row">
+              <div class="form-group">
+                <label>従業員負担率 (%) *</label>
+                <input
+                  type="number"
+                  name="employee_rate"
+                  step="0.001"
+                  min="0"
+                  max="100"
+                  required
+                  placeholder="例: 5.0 (5%)"
+                />
+              </div>
+              <div class="form-group">
+                <label>会社負担率 (%) *</label>
+                <input
+                  type="number"
+                  name="employer_rate"
+                  step="0.001"
+                  min="0"
+                  max="100"
+                  required
+                  placeholder="例: 5.0 (5%)"
+                />
+              </div>
+            </div>
+
+            <div class="form-group">
+              <label>介護保険適用年齢下限</label>
+              <input
+                type="number"
+                name="care_insurance_age_threshold"
+                min="0"
+                max="100"
+                placeholder="例: 40 (40歳以上が対象。介護保険以外は空欄)"
+              />
+              <small style="color: #666"
+                >※介護保険の場合のみ入力してください。この年齢以上の従業員に介護保険料が適用されます。</small
+              >
+            </div>
+
+            <div class="form-group">
+              <label>備考</label>
+              <textarea
+                name="notes"
+                rows="2"
+                placeholder="例: 健康保険料率 10.00% (労使折半)"
+              ></textarea>
+            </div>
+
+            <button type="submit" class="btn btn-primary">登録</button>
+            <button
+              type="button"
+              class="btn btn-secondary"
+              onclick="hideInsuranceForm()"
+            >
+              キャンセル
+            </button>
+          </form>
+        </div>
+      </div>
+
+      <!-- 子ども・子育て拠出金タブ -->
+      <div id="tab-child-support" class="tab-content">
+        <h2>子ども・子育て拠出金率設定</h2>
+
+        <div class="info-box">
+          <strong>子ども・子育て拠出金について:</strong>
+          <ul style="margin: 10px 0 0 20px">
+            <li>事業主のみが負担する拠出金です（従業員負担なし）</li>
+            <li>標準報酬月額の上限額を設定できます</li>
+            <li>年度ごとに料率を設定します</li>
+          </ul>
+        </div>
+
+        <button class="btn btn-primary" onclick="showChildSupportForm()">
+          新規追加
+        </button>
+        <div id="childSupportList"></div>
+
+        <div id="childSupportForm" class="modal-form">
+          <h3 id="childSupportFormTitle">子ども・子育て拠出金率の登録</h3>
+          <form
+            id="childSupportRateForm"
+            onsubmit="saveChildSupportRate(event)"
+          >
+            <input
+              type="hidden"
+              name="contribution_id"
+              id="editContributionId"
+            />
+            <input
+              type="hidden"
+              name="edit_mode"
+              id="editModeChild"
+              value="false"
+            />
+            <div class="form-row">
+              <div class="form-group">
+                <label>年度 *</label>
+                <input
+                  type="number"
+                  name="rate_year"
+                  min="2020"
+                  max="2050"
+                  required
+                  placeholder="例: 2026"
+                />
+              </div>
+              <div class="form-group">
+                <label>拠出金率 (%) *</label>
+                <input
+                  type="number"
+                  name="contribution_rate"
+                  step="0.001"
+                  min="0"
+                  max="100"
+                  required
+                  placeholder="例: 0.36 (0.36%)"
+                />
+              </div>
+            </div>
+
+            <div class="form-group">
+              <label>標準報酬月額上限 (円) *</label>
+              <input
+                type="number"
+                name="income_threshold"
+                min="0"
+                required
+                placeholder="例: 1500000 (150万円)"
+              />
+            </div>
+
+            <div class="form-group">
+              <label>備考</label>
+              <textarea
+                name="notes"
+                rows="2"
+                placeholder="例: 子ども・子育て拠出金率 0.36% (事業主のみ負担)"
+              ></textarea>
+            </div>
+
+            <button type="submit" class="btn btn-primary">登録</button>
+            <button
+              type="button"
+              class="btn btn-secondary"
+              onclick="hideChildSupportForm()"
+            >
+              キャンセル
+            </button>
+          </form>
+        </div>
+      </div>
+
+      <!-- 上限設定タブ -->
+      <div id="tab-limits" class="tab-content">
+        <h2>社会保険料上限設定</h2>
+
+        <div class="info-box">
+          <strong>上限設定について:</strong>
+          <ul style="margin: 10px 0 0 20px">
+            <li>健康保険と厚生年金の標準報酬月額上限を設定します</li>
+            <li>通勤手当の非課税限度額を設定します</li>
+            <li>年度ごとに変更される場合があります</li>
+          </ul>
+        </div>
+
+        <button class="btn btn-primary" onclick="showLimitForm()">
+          新規追加
+        </button>
+        <div id="limitsList"></div>
+
+        <div id="limitForm" class="modal-form">
+          <h3 id="limitFormTitle">上限設定の登録</h3>
+          <form id="limitSettingForm" onsubmit="saveLimitSetting(event)">
+            <input type="hidden" name="limit_id" id="editLimitId" />
+            <input
+              type="hidden"
+              name="edit_mode"
+              id="editModeLimit"
+              value="false"
+            />
+            <div class="form-group">
+              <label>設定種別 *</label>
+              <select name="setting_type" required>
+                <option value="">選択してください</option>
+                <option value="健康保険標準報酬月額上限">
+                  健康保険標準報酬月額上限
+                </option>
+                <option value="厚生年金標準報酬月額上限">
+                  厚生年金標準報酬月額上限
+                </option>
+                <option value="健康保険標準賞与額上限">
+                  健康保険標準賞与額上限（年間累計）
+                </option>
+                <option value="厚生年金標準賞与額上限">
+                  厚生年金標準賞与額上限（月額）
+                </option>
+                <option value="通勤手当非課税限度額">
+                  通勤手当非課税限度額
+                </option>
+              </select>
+            </div>
+
+            <div class="form-group">
+              <label>上限額 (円) *</label>
+              <input
+                type="number"
+                name="limit_amount"
+                min="0"
+                required
+                placeholder="例: 1390000"
+              />
+            </div>
+
+            <div class="form-row">
+              <div class="form-group">
+                <label>適用開始日 *</label>
+                <input type="date" name="valid_from" required />
+              </div>
+              <div class="form-group">
+                <label>適用終了日</label>
+                <input type="date" name="valid_to" />
+              </div>
+            </div>
+
+            <div class="form-group">
+              <label>備考</label>
+              <textarea name="notes" rows="2"></textarea>
+            </div>
+
+            <button type="submit" class="btn btn-primary">登録</button>
+            <button
+              type="button"
+              class="btn btn-secondary"
+              onclick="hideLimitForm()"
+            >
+              キャンセル
+            </button>
+          </form>
+        </div>
+      </div>
+
+      <!-- 所得税率表タブ -->
+      <div id="tab-tax" class="tab-content">
+        <h2>所得税率表</h2>
+        <div class="form-group" style="max-width: 300px">
+          <label>扶養人数でフィルター</label>
+          <select id="filterDependents" onchange="loadIncomeTax()">
+            <option value="">全て</option>
+            <option value="0">0人</option>
+            <option value="1">1人</option>
+            <option value="2">2人</option>
+            <option value="3">3人</option>
+            <option value="4">4人</option>
+            <option value="5">5人以上</option>
+          </select>
+        </div>
+        <button
+          class="btn btn-primary"
+          onclick="document.getElementById('csvFile').click()"
+        >
+          Excel/CSVインポート
+        </button>
+        <input
+          type="file"
+          id="csvFile"
+          accept=".csv,.xlsx,.xls"
+          style="display: none"
+          onchange="importTaxTable(event)"
+        />
+        <div id="taxList"></div>
+      </div>
+    </div>
+
+    <script>
+      const API_BASE = "http://localhost:18080";
+
+      // =====================================================
+      // タブ切り替え
+      // =====================================================
+      function showTab(tabName) {
+        document
+          .querySelectorAll(".nav-tab")
+          .forEach((tab) => tab.classList.remove("active"));
+        document
+          .querySelectorAll(".tab-content")
+          .forEach((content) => content.classList.remove("active"));
+
+        const tabs = {
+          insurance: 0,
+          "child-support": 1,
+          limits: 2,
+          tax: 3,
+        };
+
+        document
+          .querySelectorAll(".nav-tab")
+          [tabs[tabName]].classList.add("active");
+        document.getElementById(`tab-${tabName}`).classList.add("active");
+
+        // データをロード
+        if (tabName === "insurance") {
+          loadInsuranceRates();
+        } else if (tabName === "child-support") {
+          loadChildSupportRates();
+        } else if (tabName === "limits") {
+          loadLimitSettings();
+        } else if (tabName === "tax") {
+          loadIncomeTax();
+        }
+      }
+
+      // =====================================================
+      // 保険料率関連
+      // =====================================================
+      function showInsuranceForm() {
+        document.getElementById("insuranceForm").style.display = "block";
+      }
+
+      function hideInsuranceForm() {
+        document.getElementById("insuranceForm").style.display = "none";
+        document.querySelector("#insuranceForm form").reset();
+      }
+
+      async function loadInsuranceRates() {
+        try {
+          // フィルター値を取得
+          const year =
+            document.getElementById("filterInsuranceYear")?.value || "";
+          const target =
+            document.getElementById("filterCalculationTarget")?.value || "";
+          const prefecture =
+            document.getElementById("filterPrefecture")?.value || "";
+
+          // クエリパラメータを構築
+          const params = new URLSearchParams();
+          if (year) params.append("rate_year", year);
+          if (target) params.append("calculation_target", target);
+          if (prefecture) params.append("prefecture", prefecture);
+
+          const queryString = params.toString();
+          const url = `${API_BASE}/payroll/settings/insurance-rates${
+            queryString ? "?" + queryString : ""
+          }`;
+
+          const response = await fetch(url);
+          const rates = await response.json();
+
+          if (rates.length === 0) {
+            document.getElementById("insuranceList").innerHTML =
+              "<p>データがありません。</p>";
+            return;
+          }
+
+          const html = `
+            <table>
+              <thead>
+                <tr>
+                  <th>年度</th>
+                  <th>計算対象</th>
+                  <th>保険種類</th>
+                  <th>都道府県</th>
+                  <th>従業員負担率</th>
+                  <th>会社負担率</th>
+                  <th>合計税率</th>
+                  <th>介護保険年齢</th>
+                  <th>備考</th>
+                  <th>操作</th>
+                </tr>
+              </thead>
+              <tbody>
+                ${rates
+                  .map((rate) => {
+                    const employeeRate = parseFloat(rate.employee_rate);
+                    const employerRate = parseFloat(rate.employer_rate);
+                    const totalRate = employeeRate + employerRate;
+                    return `
+                    <tr>
+                      <td>${rate.rate_year}</td>
+                      <td>${rate.calculation_target}</td>
+                      <td>${rate.rate_type}</td>
+                      <td>${rate.prefecture}</td>
+                      <td>${(employeeRate * 100).toFixed(3)}%</td>
+                      <td>${(employerRate * 100).toFixed(3)}%</td>
+                      <td><strong>${(totalRate * 100).toFixed(3)}%</strong></td>
+                      <td>${
+                        rate.care_insurance_age_threshold
+                          ? rate.care_insurance_age_threshold + "歳以上"
+                          : "-"
+                      }</td>
+                      <td>${rate.notes || "-"}</td>
+                      <td>
+                        <button class="btn btn-primary btn-small" onclick="editInsuranceRate(${
+                          rate.rate_id
+                        })">編集</button>
+                        <button class="btn btn-danger btn-small" onclick="deleteInsuranceRate(${
+                          rate.rate_id
+                        })">削除</button>
+                      </td>
+                    </tr>
+                  `;
+                  })
+                  .join("")}
+              </tbody>
+            </table>
+          `;
+
+          document.getElementById("insuranceList").innerHTML = html;
+        } catch (error) {
+          alert("保険料率の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function editInsuranceRate(rateId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/insurance-rates`
+          );
+          const rates = await response.json();
+          const rate = rates.find((r) => r.rate_id === rateId);
+
+          if (!rate) {
+            alert("データが見つかりません");
+            return;
+          }
+
+          // フォームを編集モードに切り替え
+          document.getElementById("insuranceFormTitle").innerText =
+            "保険料率の編集";
+          document.getElementById("editMode").value = "true";
+          document.getElementById("editRateId").value = rateId;
+
+          // フォームにデータを入力
+          const form = document.getElementById("insuranceRateForm");
+          form.querySelector('[name="rate_year"]').value = rate.rate_year;
+          form.querySelector('[name="calculation_target"]').value =
+            rate.calculation_target;
+          form.querySelector('[name="rate_type"]').value = rate.rate_type;
+          form.querySelector('[name="prefecture"]').value = rate.prefecture;
+          form.querySelector('[name="employee_rate"]').value = (
+            rate.employee_rate * 100
+          ).toFixed(3);
+          form.querySelector('[name="employer_rate"]').value = (
+            rate.employer_rate * 100
+          ).toFixed(3);
+          form.querySelector('[name="care_insurance_age_threshold"]').value =
+            rate.care_insurance_age_threshold || "";
+          form.querySelector('[name="notes"]').value = rate.notes || "";
+
+          // フォームを表示
+          document.getElementById("insuranceForm").style.display = "block";
+        } catch (error) {
+          alert("データの取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function saveInsuranceRate(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = Object.fromEntries(formData.entries());
+
+        const isEditMode = data.edit_mode === "true";
+        const rateId = data.rate_id;
+
+        console.log("=== 保存前のデータ ===");
+        console.log("編集モード:", isEditMode);
+        console.log("Rate ID:", rateId);
+        console.log("従業員負担率 (入力値):", data.employee_rate);
+        console.log("会社負担率 (入力値):", data.employer_rate);
+
+        // 不要なフィールドを削除
+        delete data.edit_mode;
+        delete data.rate_id;
+
+        // パーセントを小数に変換
+        data.employee_rate = parseFloat(data.employee_rate) / 100;
+        data.employer_rate = parseFloat(data.employer_rate) / 100;
+
+        console.log("従業員負担率 (変換後):", data.employee_rate);
+        console.log("会社負担率 (変換後):", data.employer_rate);
+
+        // 年度と計算対象を数値/文字列に変換
+        data.rate_year = parseInt(data.rate_year);
+
+        // 介護保険年齢を数値に変換（空の場合はnull）
+        if (data.care_insurance_age_threshold) {
+          data.care_insurance_age_threshold = parseInt(
+            data.care_insurance_age_threshold
+          );
+        } else {
+          data.care_insurance_age_threshold = null;
+        }
+
+        // 空の値を除外
+        if (!data.notes) delete data.notes;
+
+        console.log(
+          "送信するURL:",
+          isEditMode
+            ? `${API_BASE}/payroll/settings/insurance-rates/${rateId}`
+            : `${API_BASE}/payroll/settings/insurance-rates`
+        );
+        console.log("送信するデータ:", JSON.stringify(data, null, 2));
+
+        try {
+          const url = isEditMode
+            ? `${API_BASE}/payroll/settings/insurance-rates/${rateId}`
+            : `${API_BASE}/payroll/settings/insurance-rates`;
+          const method = isEditMode ? "PUT" : "POST";
+
+          console.log("HTTPメソッド:", method);
+
+          const response = await fetch(url, {
+            method: method,
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(data),
+          });
+
+          console.log("レスポンスステータス:", response.status);
+
+          if (response.ok) {
+            const result = await response.json();
+            console.log("成功レスポンス:", result);
+            alert(
+              isEditMode ? "保険料率を更新しました" : "保険料率を登録しました"
+            );
+            hideInsuranceForm();
+            loadInsuranceRates();
+          } else {
+            const error = await response.json();
+            console.error("エラーレスポンス:", error);
+            alert(
+              (isEditMode ? "更新" : "登録") +
+                "に失敗しました: " +
+                JSON.stringify(error.detail)
+            );
+          }
+        } catch (error) {
+          console.error("例外が発生:", error);
+          alert((isEditMode ? "更新" : "登録") + "に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function deleteInsuranceRate(rateId) {
+        if (!confirm("この保険料率を削除してもよろしいですか？")) return;
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/insurance-rates/${rateId}`,
+            { method: "DELETE" }
+          );
+
+          if (response.ok) {
+            alert("削除しました");
+            loadInsuranceRates();
+          } else {
+            alert("削除に失敗しました");
+          }
+        } catch (error) {
+          alert("削除に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // =====================================================
+      // 子ども・子育て拠出金関連
+      // =====================================================
+      function showChildSupportForm() {
+        document.getElementById("childSupportForm").style.display = "block";
+      }
+
+      function hideChildSupportForm() {
+        document.getElementById("childSupportForm").style.display = "none";
+        document.getElementById("childSupportFormTitle").innerText =
+          "子ども・子育て拠出金率の登録";
+        document.getElementById("editModeChild").value = "false";
+        document.getElementById("editContributionId").value = "";
+        document.getElementById("childSupportRateForm").reset();
+      }
+
+      async function loadChildSupportRates() {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/child-support-rates`
+          );
+          const rates = await response.json();
+
+          if (rates.length === 0) {
+            document.getElementById("childSupportList").innerHTML =
+              "<p>データがありません。</p>";
+            return;
+          }
+
+          const html = `
+            <table>
+              <thead>
+                <tr>
+                  <th>年度</th>
+                  <th>標準報酬月額上限</th>
+                  <th>拠出金率</th>
+                  <th>備考</th>
+                  <th>操作</th>
+                </tr>
+              </thead>
+              <tbody>
+                ${rates
+                  .map(
+                    (rate) => `
+                    <tr>
+                      <td>${rate.rate_year}</td>
+                      <td>¥${Number(
+                        rate.income_threshold
+                      ).toLocaleString()}</td>
+                      <td>${(parseFloat(rate.contribution_rate) * 100).toFixed(
+                        3
+                      )}%</td>
+                      <td>${rate.notes || "-"}</td>
+                      <td>
+                        <button class="btn btn-primary btn-small" onclick="editChildSupportRate(${
+                          rate.contribution_id
+                        })">編集</button>
+                        <button class="btn btn-danger btn-small" onclick="deleteChildSupportRate(${
+                          rate.contribution_id
+                        })">削除</button>
+                      </td>
+                    </tr>
+                  `
+                  )
+                  .join("")}
+              </tbody>
+            </table>
+          `;
+
+          document.getElementById("childSupportList").innerHTML = html;
+        } catch (error) {
+          alert("子ども・子育て拠出金率の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function editChildSupportRate(contributionId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/child-support-rates`
+          );
+          const rates = await response.json();
+          const rate = rates.find((r) => r.contribution_id === contributionId);
+
+          if (!rate) {
+            alert("データが見つかりません");
+            return;
+          }
+
+          // フォームを編集モードに切り替え
+          document.getElementById("childSupportFormTitle").innerText =
+            "子ども・子育て拠出金率の編集";
+          document.getElementById("editModeChild").value = "true";
+          document.getElementById("editContributionId").value = contributionId;
+
+          // フォームにデータを入力
+          const form = document.getElementById("childSupportRateForm");
+          form.querySelector('[name="rate_year"]').value = rate.rate_year;
+          form.querySelector('[name="income_threshold"]').value =
+            rate.income_threshold;
+          form.querySelector('[name="contribution_rate"]').value = (
+            rate.contribution_rate * 100
+          ).toFixed(3);
+          form.querySelector('[name="notes"]').value = rate.notes || "";
+
+          // フォームを表示
+          document.getElementById("childSupportForm").style.display = "block";
+        } catch (error) {
+          alert("データの取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function saveChildSupportRate(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = Object.fromEntries(formData.entries());
+
+        const isEditMode = data.edit_mode === "true";
+        const contributionId = data.contribution_id;
+
+        // 不要なフィールドを削除
+        delete data.edit_mode;
+        delete data.contribution_id;
+
+        // データ型変換
+        data.rate_year = parseInt(data.rate_year);
+        data.income_threshold = parseFloat(data.income_threshold);
+        data.contribution_rate = parseFloat(data.contribution_rate) / 100;
+
+        // 空の値を除外
+        if (!data.notes) delete data.notes;
+
+        try {
+          const url = isEditMode
+            ? `${API_BASE}/payroll/settings/child-support-rates/${contributionId}`
+            : `${API_BASE}/payroll/settings/child-support-rates`;
+          const method = isEditMode ? "PUT" : "POST";
+
+          const response = await fetch(url, {
+            method: method,
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(data),
+          });
+
+          if (response.ok) {
+            alert(
+              isEditMode
+                ? "子ども・子育て拠出金率を更新しました"
+                : "子ども・子育て拠出金率を登録しました"
+            );
+            hideChildSupportForm();
+            loadChildSupportRates();
+          } else {
+            const error = await response.json();
+            alert(
+              (isEditMode ? "更新" : "登録") +
+                "に失敗しました: " +
+                JSON.stringify(error.detail)
+            );
+          }
+        } catch (error) {
+          alert((isEditMode ? "更新" : "登録") + "に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function deleteChildSupportRate(contributionId) {
+        if (!confirm("この拠出金率を削除してもよろしいですか？")) return;
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/child-support-rates/${contributionId}`,
+            { method: "DELETE" }
+          );
+
+          if (response.ok) {
+            alert("削除しました");
+            loadChildSupportRates();
+          } else {
+            alert("削除に失敗しました");
+          }
+        } catch (error) {
+          alert("削除に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // =====================================================
+      // 上限設定関連
+      // =====================================================
+      function showLimitForm() {
+        document.getElementById("limitForm").style.display = "block";
+      }
+
+      function hideLimitForm() {
+        document.getElementById("limitForm").style.display = "none";
+        document.getElementById("limitFormTitle").innerText = "上限設定の登録";
+        document.getElementById("editModeLimit").value = "false";
+        document.getElementById("editLimitId").value = "";
+        document.getElementById("limitSettingForm").reset();
+      }
+
+      async function loadLimitSettings() {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/insurance-limits`
+          );
+          const limits = await response.json();
+
+          if (limits.length === 0) {
+            document.getElementById("limitsList").innerHTML =
+              "<p>データがありません。</p>";
+            return;
+          }
+
+          const html = `
+            <table>
+              <thead>
+                <tr>
+                  <th>設定種別</th>
+                  <th>上限額</th>
+                  <th>適用期間</th>
+                  <th>備考</th>
+                  <th>操作</th>
+                </tr>
+              </thead>
+              <tbody>
+                ${limits
+                  .map(
+                    (limit) => `
+                    <tr>
+                      <td>${limit.setting_type}</td>
+                      <td>¥${Number(limit.limit_amount).toLocaleString()}</td>
+                      <td>${limit.valid_from} ～ ${
+                      limit.valid_to || "現在"
+                    }</td>
+                      <td>${limit.notes || "-"}</td>
+                      <td>
+                        <button class="btn btn-primary btn-small" onclick="editLimitSetting(${
+                          limit.limit_id
+                        })">編集</button>
+                        <button class="btn btn-danger btn-small" onclick="deleteLimitSetting(${
+                          limit.limit_id
+                        })">削除</button>
+                      </td>
+                    </tr>
+                  `
+                  )
+                  .join("")}
+              </tbody>
+            </table>
+          `;
+
+          document.getElementById("limitsList").innerHTML = html;
+        } catch (error) {
+          alert("上限設定の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function editLimitSetting(limitId) {
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/insurance-limits`
+          );
+          const limits = await response.json();
+          const limit = limits.find((l) => l.limit_id === limitId);
+
+          if (!limit) {
+            alert("データが見つかりません");
+            return;
+          }
+
+          // フォームを編集モードに切り替え
+          document.getElementById("limitFormTitle").innerText =
+            "上限設定の編集";
+          document.getElementById("editModeLimit").value = "true";
+          document.getElementById("editLimitId").value = limitId;
+
+          // フォームにデータを入力
+          const form = document.getElementById("limitSettingForm");
+          form.querySelector('[name="setting_type"]').value =
+            limit.setting_type;
+          form.querySelector('[name="limit_amount"]').value =
+            limit.limit_amount;
+          form.querySelector('[name="valid_from"]').value = limit.valid_from;
+          form.querySelector('[name="valid_to"]').value = limit.valid_to || "";
+          form.querySelector('[name="notes"]').value = limit.notes || "";
+
+          // フォームを表示
+          document.getElementById("limitForm").style.display = "block";
+        } catch (error) {
+          alert("データの取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function saveLimitSetting(event) {
+        event.preventDefault();
+        const form = event.target;
+        const formData = new FormData(form);
+        const data = Object.fromEntries(formData.entries());
+
+        const isEditMode = data.edit_mode === "true";
+        const limitId = data.limit_id;
+
+        // 不要なフィールドを削除
+        delete data.edit_mode;
+        delete data.limit_id;
+
+        // データ型変換
+        data.limit_amount = parseFloat(data.limit_amount);
+
+        // 空の値を除外
+        if (!data.valid_to) delete data.valid_to;
+        if (!data.notes) delete data.notes;
+
+        try {
+          const url = isEditMode
+            ? `${API_BASE}/payroll/settings/insurance-limits/${limitId}`
+            : `${API_BASE}/payroll/settings/insurance-limits`;
+          const method = isEditMode ? "PUT" : "POST";
+
+          const response = await fetch(url, {
+            method: method,
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(data),
+          });
+
+          if (response.ok) {
+            alert(
+              isEditMode ? "上限設定を更新しました" : "上限設定を登録しました"
+            );
+            hideLimitForm();
+            loadLimitSettings();
+          } else {
+            const error = await response.json();
+            alert(
+              (isEditMode ? "更新" : "登録") +
+                "に失敗しました: " +
+                JSON.stringify(error.detail)
+            );
+          }
+        } catch (error) {
+          alert((isEditMode ? "更新" : "登録") + "に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function deleteLimitSetting(limitId) {
+        if (!confirm("この上限設定を削除してもよろしいですか？")) return;
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/insurance-limits/${limitId}`,
+            { method: "DELETE" }
+          );
+
+          if (response.ok) {
+            alert("削除しました");
+            loadLimitSettings();
+          } else {
+            alert("削除に失敗しました");
+          }
+        } catch (error) {
+          alert("削除に失敗しました");
+          console.error(error);
+        }
+      }
+
+      // =====================================================
+      // 所得税率表関連
+      // =====================================================
+
+      // =====================================================
+      // 所得税率表関連
+      // =====================================================
+      async function loadIncomeTax() {
+        const dependentsFilter =
+          document.getElementById("filterDependents").value;
+        const params = dependentsFilter
+          ? `?dependents_count=${dependentsFilter}`
+          : "";
+
+        try {
+          const response = await fetch(
+            `${API_BASE}/payroll/settings/income-tax${params}`
+          );
+          const taxes = await response.json();
+
+          if (taxes.length === 0) {
+            document.getElementById("taxList").innerHTML =
+              "<p>データがありません。</p>";
+            return;
+          }
+
+          const html = `
+            <table>
+              <thead>
+                <tr>
+                  <th>扶養人数</th>
+                  <th>月収From</th>
+                  <th>月収To</th>
+                  <th>税額</th>
+                  <th>適用期間</th>
+                </tr>
+              </thead>
+              <tbody>
+                ${taxes
+                  .map(
+                    (tax) => `
+                    <tr>
+                      <td>${tax.dependents_count}人</td>
+                      <td>¥${Number(
+                        tax.monthly_income_from
+                      ).toLocaleString()}</td>
+                      <td>¥${Number(
+                        tax.monthly_income_to
+                      ).toLocaleString()}</td>
+                      <td>¥${Number(tax.tax_amount).toLocaleString()}</td>
+                      <td>${tax.valid_from} ～ ${tax.valid_to || "現在"}</td>
+                    </tr>
+                  `
+                  )
+                  .join("")}
+              </tbody>
+            </table>
+          `;
+
+          document.getElementById("taxList").innerHTML = html;
+        } catch (error) {
+          alert("所得税率表の取得に失敗しました");
+          console.error(error);
+        }
+      }
+
+      async function importTaxTable(event) {
+        const file = event.target.files[0];
+        if (!file) return;
+
+        const formData = new FormData();
+        formData.append("file", file);
+
+        const taxYear = prompt(
+          "税年度を入力してください（空欄の場合はファイルから自動抽出）:",
+          ""
+        );
+
+        try {
+          let url = `${API_BASE}/payroll/settings/income-tax/import`;
+          if (taxYear && taxYear.trim()) {
+            url += `?tax_year=${taxYear.trim()}`;
+          }
+
+          const response = await fetch(url, {
+            method: "POST",
+            body: formData,
+          });
+
+          if (response.ok) {
+            const result = await response.json();
+            alert(result.message + `\n年度: ${result.year}`);
+            loadIncomeTax();
+          } else {
+            const error = await response.json();
+            alert("インポートに失敗しました: " + JSON.stringify(error.detail));
+          }
+        } catch (error) {
+          alert("インポートに失敗しました");
+          console.error(error);
+        }
+
+        event.target.value = "";
+      }
+
+      // =====================================================
+      // 初期化
+      // =====================================================
+      document.addEventListener("DOMContentLoaded", function () {
+        loadInsuranceRates();
+      });
+    </script>
+  </body>
+</html>
diff --git a/frontend/payroll.html b/frontend/payroll.html
new file mode 100644
index 0000000..606af90
--- /dev/null
+++ b/frontend/payroll.html
@@ -0,0 +1,121 @@
+<!DOCTYPE html>
+<html lang="ja">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>給与管理システム</title>
+    <link rel="stylesheet" href="/css/style.css" />
+    <style>
+      .menu-grid {
+        display: grid;
+        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
+        gap: 20px;
+        margin-top: 30px;
+      }
+      .menu-card {
+        padding: 30px;
+        border: 2px solid #007bff;
+        border-radius: 10px;
+        text-align: center;
+        cursor: pointer;
+        transition: all 0.3s;
+      }
+      .menu-card:hover {
+        background: #007bff;
+        color: white;
+        transform: translateY(-5px);
+        box-shadow: 0 5px 15px rgba(0, 123, 255, 0.3);
+      }
+      .menu-card h2 {
+        margin: 0 0 15px 0;
+        font-size: 1.5em;
+      }
+      .menu-card p {
+        margin: 0;
+        opacity: 0.8;
+      }
+      .menu-card:hover p {
+        opacity: 1;
+      }
+      .icon {
+        font-size: 3em;
+        margin-bottom: 15px;
+      }
+      .back-link {
+        display: inline-block;
+        margin-bottom: 20px;
+        color: #007bff;
+        text-decoration: none;
+      }
+      .back-link:hover {
+        text-decoration: underline;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="container">
+      <a href="../index.html" class="back-link">← メインメニューに戻る</a>
+
+      <h1>給与管理システム</h1>
+      <p>従業員の給与計算、扶養管理、保険料・税金の管理を行います</p>
+
+      <div class="menu-grid">
+        <div class="menu-card" onclick="location.href='payroll-employees.html'">
+          <div class="icon">👥</div>
+          <h2>従業員管理</h2>
+          <p>従業員の基本情報、扶養家族情報を管理します</p>
+        </div>
+
+        <div
+          class="menu-card"
+          onclick="location.href='payroll-salary-settings.html'"
+        >
+          <div class="icon">💰</div>
+          <h2>給与設定</h2>
+          <p>各従業員の給与設定、基本給、手当などを管理します</p>
+        </div>
+
+        <div
+          class="menu-card"
+          onclick="location.href='payroll-calculation.html'"
+        >
+          <div class="icon">🧮</div>
+          <h2>月次給与計算</h2>
+          <p>毎月の給与計算、給与明細の作成・承認を行います</p>
+        </div>
+
+        <div class="menu-card" onclick="location.href='payroll-settings.html'">
+          <div class="icon">⚙️</div>
+          <h2>税率・保険料設定</h2>
+          <p>社会保険料率、所得税率表の管理を行います</p>
+        </div>
+      </div>
+
+      <div
+        style="
+          margin-top: 50px;
+          padding: 20px;
+          background: #f0f8ff;
+          border-radius: 5px;
+        "
+      >
+        <h3>📋 給与システムの使い方</h3>
+        <ol>
+          <li>
+            <strong>従業員管理</strong
+            >で従業員を登録し、扶養家族情報を入力します
+          </li>
+          <li><strong>給与設定</strong>で各従業員の基本給や手当を設定します</li>
+          <li>
+            <strong>税率・保険料設定</strong
+            >で社会保険料率や所得税率表を確認・更新します
+          </li>
+          <li>
+            <strong>月次給与計算</strong
+            >で勤怠情報を入力し、給与を計算・承認します
+          </li>
+        </ol>
+      </div>
+    </div>
+  </body>
+</html>
diff --git a/reports/tmp/01-07 (3).xls b/reports/tmp/01-07 (3).xls
new file mode 100644
index 0000000..0b4696a
Binary files /dev/null and b/reports/tmp/01-07 (3).xls differ
diff --git a/メモ.txt b/メモ.txt
index 618329f..c58aa64 100644
--- a/メモ.txt
+++ b/メモ.txt
@@ -78,6 +78,8 @@ command = C:\Users\zxh_y\AppData\Local\Programs\Python\Python312\python.exe -m v
 cd C:\workspace\njts-accounting-core\backend
 .venv\Scripts\activate
 uvicorn app.main:app --reload --host 127.0.0.1 --port 18080
+uvicorn app.main:app --reload --host 127.0.0.1 --port 18080
+& .\.venv\Scripts\python.exe -m uvicorn app.main:app --reload --host 127.0.0.1 --port 18080
 
 http://localhost:18080/docs