diff --git a/backend/services/identity-service/prisma/migrations/20260305000000_add_payment_password_hash/migration.sql b/backend/services/identity-service/prisma/migrations/20260305000000_add_payment_password_hash/migration.sql
new file mode 100644
index 00000000..8851f3f4
--- /dev/null
+++ b/backend/services/identity-service/prisma/migrations/20260305000000_add_payment_password_hash/migration.sql
@@ -0,0 +1,2 @@
+-- AlterTable: 新增支付密码哈希字段
+ALTER TABLE "user_accounts" ADD COLUMN "payment_password_hash" VARCHAR(100);
diff --git a/backend/services/identity-service/prisma/schema.prisma b/backend/services/identity-service/prisma/schema.prisma
index 6369b28f..5b43ba9d 100644
--- a/backend/services/identity-service/prisma/schema.prisma
+++ b/backend/services/identity-service/prisma/schema.prisma
@@ -17,7 +17,8 @@ model UserAccount {
   email           String?  @unique @db.VarChar(100)  // 绑定的邮箱地址
   emailVerified   Boolean  @default(false) @map("email_verified")  // 邮箱是否验证
   emailVerifiedAt DateTime? @map("email_verified_at")  // 邮箱验证时间
-  passwordHash    String?  @map("password_hash") @db.VarChar(100)  // bcrypt 哈希密码
+  passwordHash        String?  @map("password_hash") @db.VarChar(100)  // bcrypt 哈希登录密码
+  paymentPasswordHash String?  @map("payment_password_hash") @db.VarChar(100)  // bcrypt 哈希支付密码
   nickname        String   @db.VarChar(100)
   avatarUrl       String?  @map("avatar_url") @db.Text
 
diff --git a/backend/services/identity-service/src/api/controllers/user-account.controller.ts b/backend/services/identity-service/src/api/controllers/user-account.controller.ts
index 8daae251..432777f9 100644
--- a/backend/services/identity-service/src/api/controllers/user-account.controller.ts
+++ b/backend/services/identity-service/src/api/controllers/user-account.controller.ts
@@ -756,6 +756,77 @@ export class UserAccountController {
     return { valid };
   }
 
+  // ============ 支付密码相关 ============
+
+  @Get('payment-password-status')
+  @ApiBearerAuth()
+  @ApiOperation({
+    summary: '查询支付密码状态',
+    description: '查询当前用户是否已设置支付密码',
+  })
+  @ApiResponse({ status: 200, description: '{ isSet: boolean }' })
+  async getPaymentPasswordStatus(@CurrentUser() user: CurrentUserData) {
+    const isSet = await this.userService.isPaymentPasswordSet(user.userId);
+    return { isSet };
+  }
+
+  @Post('set-payment-password')
+  @ApiBearerAuth()
+  @ApiOperation({
+    summary: '设置支付密码',
+    description: '首次设置支付密码（无需旧密码）',
+  })
+  @ApiResponse({ status: 200, description: '设置成功' })
+  @ApiResponse({ status: 400, description: '支付密码已设置' })
+  async setPaymentPassword(
+    @CurrentUser() user: CurrentUserData,
+    @Body() body: { password: string },
+  ) {
+    await this.userService.setPaymentPassword({
+      userId: user.userId,
+      password: body.password,
+    });
+    return { message: '支付密码设置成功' };
+  }
+
+  @Post('change-payment-password')
+  @ApiBearerAuth()
+  @ApiOperation({
+    summary: '修改支付密码',
+    description: '验证旧支付密码后修改为新支付密码',
+  })
+  @ApiResponse({ status: 200, description: '修改成功' })
+  @ApiResponse({ status: 400, description: '旧支付密码错误' })
+  async changePaymentPassword(
+    @CurrentUser() user: CurrentUserData,
+    @Body() body: { oldPassword: string; newPassword: string },
+  ) {
+    await this.userService.changePaymentPassword({
+      userId: user.userId,
+      oldPassword: body.oldPassword,
+      newPassword: body.newPassword,
+    });
+    return { message: '支付密码修改成功' };
+  }
+
+  @Post('verify-payment-password')
+  @ApiBearerAuth()
+  @ApiOperation({
+    summary: '验证支付密码',
+    description: '验证用户的支付密码，用于认种/预种等支付操作二次验证',
+  })
+  @ApiResponse({ status: 200, description: '{ valid: boolean }' })
+  async verifyPaymentPassword(
+    @CurrentUser() user: CurrentUserData,
+    @Body() body: { password: string },
+  ) {
+    const valid = await this.userService.verifyPaymentPassword(
+      user.userId,
+      body.password,
+    );
+    return { valid };
+  }
+
   @Get('users/resolve-address/:accountSequence')
   @ApiBearerAuth()
   @ApiOperation({
diff --git a/backend/services/identity-service/src/application/services/user-application.service.ts b/backend/services/identity-service/src/application/services/user-application.service.ts
index 129b2f65..5fdefe4b 100644
--- a/backend/services/identity-service/src/application/services/user-application.service.ts
+++ b/backend/services/identity-service/src/application/services/user-application.service.ts
@@ -2856,6 +2856,106 @@ export class UserApplicationService {
     return isValid;
   }
 
+  // ============ 支付密码相关 ============
+
+  /**
+   * 查询是否已设置支付密码
+   */
+  async isPaymentPasswordSet(userId: string): Promise<boolean> {
+    const user = await this.prisma.userAccount.findUnique({
+      where: { userId: BigInt(userId) },
+      select: { paymentPasswordHash: true },
+    });
+    return !!user?.paymentPasswordHash;
+  }
+
+  /**
+   * 设置支付密码（首次设置，无需旧密码）
+   */
+  async setPaymentPassword(command: {
+    userId: string;
+    password: string;
+  }): Promise<void> {
+    this.logger.log(`Setting payment password for user: ${command.userId}`);
+
+    const user = await this.prisma.userAccount.findUnique({
+      where: { userId: BigInt(command.userId) },
+      select: { paymentPasswordHash: true },
+    });
+
+    if (user?.paymentPasswordHash) {
+      throw new ApplicationError('支付密码已设置，请使用修改支付密码功能');
+    }
+
+    const bcrypt = await import('bcrypt');
+    const paymentPasswordHash = await bcrypt.hash(command.password, 10);
+
+    await this.prisma.userAccount.update({
+      where: { userId: BigInt(command.userId) },
+      data: { paymentPasswordHash },
+    });
+
+    this.logger.log(`Payment password set for user: ${command.userId}`);
+  }
+
+  /**
+   * 修改支付密码（需验证旧密码）
+   */
+  async changePaymentPassword(command: {
+    userId: string;
+    oldPassword: string;
+    newPassword: string;
+  }): Promise<void> {
+    this.logger.log(`Changing payment password for user: ${command.userId}`);
+
+    const user = await this.prisma.userAccount.findUnique({
+      where: { userId: BigInt(command.userId) },
+      select: { paymentPasswordHash: true },
+    });
+
+    if (!user?.paymentPasswordHash) {
+      throw new ApplicationError('尚未设置支付密码，请先设置');
+    }
+
+    const bcrypt = await import('bcrypt');
+    const isOldValid = await bcrypt.compare(command.oldPassword, user.paymentPasswordHash);
+    if (!isOldValid) {
+      throw new ApplicationError('旧支付密码错误');
+    }
+
+    const paymentPasswordHash = await bcrypt.hash(command.newPassword, 10);
+    await this.prisma.userAccount.update({
+      where: { userId: BigInt(command.userId) },
+      data: { paymentPasswordHash },
+    });
+
+    this.logger.log(`Payment password changed for user: ${command.userId}`);
+  }
+
+  /**
+   * 验证支付密码
+   *
+   * @returns 密码是否正确
+   */
+  async verifyPaymentPassword(userId: string, password: string): Promise<boolean> {
+    this.logger.log(`Verifying payment password for user: ${userId}`);
+
+    const user = await this.prisma.userAccount.findUnique({
+      where: { userId: BigInt(userId) },
+      select: { paymentPasswordHash: true },
+    });
+
+    if (!user?.paymentPasswordHash) {
+      throw new ApplicationError('请先设置支付密码');
+    }
+
+    const bcrypt = await import('bcrypt');
+    const isValid = await bcrypt.compare(password, user.paymentPasswordHash);
+
+    this.logger.log(`Payment password verification result for user ${userId}: ${isValid}`);
+    return isValid;
+  }
+
   /**
    * 遮蔽手机号
    */
diff --git a/frontend/mobile-app/lib/core/services/account_service.dart b/frontend/mobile-app/lib/core/services/account_service.dart
index 00771270..50367a21 100644
--- a/frontend/mobile-app/lib/core/services/account_service.dart
+++ b/frontend/mobile-app/lib/core/services/account_service.dart
@@ -2124,6 +2124,93 @@ class AccountService {
     }
   }
 
+  // ============ 支付密码相关 ============
+
+  /// 查询是否已设置支付密码 (GET /user/payment-password-status)
+  ///
+  /// 返回 true 表示已设置，false 表示未设置
+  Future<bool> isPaymentPasswordSet() async {
+    debugPrint('$_tag isPaymentPasswordSet() - 查询支付密码状态');
+    try {
+      final response = await _apiClient.get('/user/payment-password-status');
+      final isSet = response.data['isSet'] == true;
+      debugPrint('$_tag isPaymentPasswordSet() - 结果: $isSet');
+      return isSet;
+    } catch (e) {
+      debugPrint('$_tag isPaymentPasswordSet() - 异常: $e');
+      rethrow;
+    }
+  }
+
+  /// 设置支付密码（首次设置）(POST /user/set-payment-password)
+  ///
+  /// [password] 支付密码明文（建议6位数字）
+  Future<void> setPaymentPassword(String password) async {
+    debugPrint('$_tag setPaymentPassword() - 开始设置支付密码');
+    try {
+      await _apiClient.post(
+        '/user/set-payment-password',
+        data: {'password': password},
+      );
+      debugPrint('$_tag setPaymentPassword() - 支付密码设置成功');
+    } on ApiException catch (e) {
+      debugPrint('$_tag setPaymentPassword() - API 异常: $e');
+      rethrow;
+    } catch (e) {
+      debugPrint('$_tag setPaymentPassword() - 未知异常: $e');
+      throw ApiException('设置支付密码失败: $e');
+    }
+  }
+
+  /// 修改支付密码 (POST /user/change-payment-password)
+  ///
+  /// [oldPassword] 当前支付密码
+  /// [newPassword] 新支付密码
+  Future<void> changePaymentPassword({
+    required String oldPassword,
+    required String newPassword,
+  }) async {
+    debugPrint('$_tag changePaymentPassword() - 开始修改支付密码');
+    try {
+      await _apiClient.post(
+        '/user/change-payment-password',
+        data: {'oldPassword': oldPassword, 'newPassword': newPassword},
+      );
+      debugPrint('$_tag changePaymentPassword() - 支付密码修改成功');
+    } on ApiException catch (e) {
+      debugPrint('$_tag changePaymentPassword() - API 异常: $e');
+      rethrow;
+    } catch (e) {
+      debugPrint('$_tag changePaymentPassword() - 未知异常: $e');
+      throw ApiException('修改支付密码失败: $e');
+    }
+  }
+
+  /// 验证支付密码 (POST /user/verify-payment-password)
+  ///
+  /// 后端响应格式：{ "valid": true/false }
+  /// - 返回 true：密码正确
+  /// - 返回 false：密码错误
+  /// - 抛出异常：未设置支付密码或网络错误
+  Future<bool> verifyPaymentPassword(String password) async {
+    debugPrint('$_tag verifyPaymentPassword() - 开始验证支付密码');
+    try {
+      final response = await _apiClient.post(
+        '/user/verify-payment-password',
+        data: {'password': password},
+      );
+      final valid = response.data['valid'] == true;
+      debugPrint('$_tag verifyPaymentPassword() - 验证结果: $valid');
+      return valid;
+    } on ApiException catch (e) {
+      debugPrint('$_tag verifyPaymentPassword() - 验证异常: $e');
+      rethrow;
+    } catch (e) {
+      debugPrint('$_tag verifyPaymentPassword() - 未知异常: $e');
+      rethrow;
+    }
+  }
+
   // ============ 邮箱绑定相关 ============
 
   /// 获取邮箱绑定状态
diff --git a/frontend/mobile-app/lib/features/planting/presentation/pages/planting_location_page.dart b/frontend/mobile-app/lib/features/planting/presentation/pages/planting_location_page.dart
index fec8343f..9efeffae 100644
--- a/frontend/mobile-app/lib/features/planting/presentation/pages/planting_location_page.dart
+++ b/frontend/mobile-app/lib/features/planting/presentation/pages/planting_location_page.dart
@@ -243,17 +243,20 @@ class _PlantingLocationPageState extends ConsumerState<PlantingLocationPage> {
     }
   }
 
-  /// 验证登录密码后再提交认种
+  /// 验证支付密码后再提交认种 [2026-03-05]
   ///
   /// 插入在 [PlantingConfirmDialog] 确认与 [_submitPlanting] 之间：
-  /// 弹出 [PasswordVerifyDialog] → 密码正确才调用 [_submitPlanting]，
+  /// 弹出 [PasswordVerifyDialog]（支付密码模式）→ 密码正确才调用 [_submitPlanting]，
   /// 取消或验证失败则停留在当前页，不触发任何提交逻辑。
   Future<void> _verifyPasswordThenSubmit() async {
     final verified = await PasswordVerifyDialog.show(
       context: context,
+      title: '验证支付密码',
+      subtitle: '为保障资金安全，请输入您的6位支付密码以确认认种',
+      hint: '请输入支付密码',
       onVerify: (password) async {
         final accountService = ref.read(accountServiceProvider);
-        return await accountService.verifyLoginPassword(password);
+        return await accountService.verifyPaymentPassword(password);
       },
     );
     if (verified == true) {
diff --git a/frontend/mobile-app/lib/features/planting/presentation/widgets/password_verify_dialog.dart b/frontend/mobile-app/lib/features/planting/presentation/widgets/password_verify_dialog.dart
index 2df6569c..9a8bb5a8 100644
--- a/frontend/mobile-app/lib/features/planting/presentation/widgets/password_verify_dialog.dart
+++ b/frontend/mobile-app/lib/features/planting/presentation/widgets/password_verify_dialog.dart
@@ -7,28 +7,45 @@ import 'package:flutter/material.dart';
 /// 抛出异常表示网络/系统错误（由弹窗捕获并展示提示）
 typedef PasswordVerifyCallback = Future<bool> Function(String password);
 
-/// 认种密码校验弹窗
+/// 密码校验弹窗（通用）
 ///
-/// 在 [PlantingConfirmDialog] 用户点击"确认认种"之后、实际提交之前弹出，
-/// 要求用户输入登录密码进行二次身份验证，防止误操作或他人操作。
+/// 支持两种模式：
+/// - 登录密码验证（认种/预种前身份核实）
+/// - 支付密码验证（认种/预种支付二次确认）
 ///
 /// 调用方式：
 /// ```dart
+/// // 验证支付密码
 /// final verified = await PasswordVerifyDialog.show(
 ///   context: context,
-///   onVerify: (password) => accountService.verifyLoginPassword(password),
+///   title: '验证支付密码',
+///   subtitle: '请输入6位支付密码以确认认种',
+///   hint: '请输入支付密码',
+///   onVerify: (password) => accountService.verifyPaymentPassword(password),
 /// );
 /// if (verified == true) _submitPlanting();
 /// ```
 ///
-/// 后端接口：POST /user/verify-password → { valid: bool }
+/// 后端接口：POST /user/verify-payment-password → { valid: bool }
 class PasswordVerifyDialog extends StatefulWidget {
-  /// 密码校验回调，由调用方注入（通常调用 accountService.verifyLoginPassword）
+  /// 密码校验回调，由调用方注入
   final PasswordVerifyCallback onVerify;
 
+  /// 弹窗标题，默认"验证登录密码"
+  final String title;
+
+  /// 说明文字，默认"为保障账户安全，请输入您的登录密码以继续"
+  final String subtitle;
+
+  /// 输入框 hint，默认"请输入登录密码"
+  final String hint;
+
   const PasswordVerifyDialog({
     super.key,
     required this.onVerify,
+    this.title = '验证登录密码',
+    this.subtitle = '为保障账户安全，请输入您的登录密码以继续',
+    this.hint = '请输入登录密码',
   });
 
   /// 显示密码验证弹窗
@@ -36,12 +53,20 @@ class PasswordVerifyDialog extends StatefulWidget {
   static Future<bool?> show({
     required BuildContext context,
     required PasswordVerifyCallback onVerify,
+    String title = '验证登录密码',
+    String subtitle = '为保障账户安全，请输入您的登录密码以继续',
+    String hint = '请输入登录密码',
   }) {
     return showDialog<bool>(
       context: context,
       barrierDismissible: false,
       barrierColor: const Color(0x80000000),
-      builder: (context) => PasswordVerifyDialog(onVerify: onVerify),
+      builder: (context) => PasswordVerifyDialog(
+        onVerify: onVerify,
+        title: title,
+        subtitle: subtitle,
+        hint: hint,
+      ),
     );
   }
 
@@ -73,7 +98,7 @@ class _PasswordVerifyDialogState extends State<PasswordVerifyDialog> {
   Future<void> _handleConfirm() async {
     final password = _passwordController.text.trim();
     if (password.isEmpty) {
-      setState(() => _errorMessage = '请输入登录密码');
+      setState(() => _errorMessage = '请输入${widget.hint.replaceAll('请输入', '')}');
       return;
     }
 
@@ -205,9 +230,9 @@ class _PasswordVerifyDialogState extends State<PasswordVerifyDialog> {
 
   /// 构建标题
   Widget _buildTitle() {
-    return const Text(
-      '验证登录密码',
-      style: TextStyle(
+    return Text(
+      widget.title,
+      style: const TextStyle(
         fontSize: 20,
         fontFamily: 'Inter',
         fontWeight: FontWeight.w700,
@@ -221,9 +246,9 @@ class _PasswordVerifyDialogState extends State<PasswordVerifyDialog> {
 
   /// 构建说明文字
   Widget _buildSubtitle() {
-    return const Text(
-      '为保障账户安全，请输入您的登录密码以继续认种',
-      style: TextStyle(
+    return Text(
+      widget.subtitle,
+      style: const TextStyle(
         fontSize: 14,
         fontFamily: 'Inter',
         height: 1.5,
@@ -267,7 +292,7 @@ class _PasswordVerifyDialogState extends State<PasswordVerifyDialog> {
         decoration: InputDecoration(
           contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
           border: InputBorder.none,
-          hintText: '请输入登录密码',
+          hintText: widget.hint,
           hintStyle: const TextStyle(
             fontSize: 16,
             fontFamily: 'Inter',
diff --git a/frontend/mobile-app/lib/features/pre_planting/presentation/pages/pre_planting_purchase_page.dart b/frontend/mobile-app/lib/features/pre_planting/presentation/pages/pre_planting_purchase_page.dart
index f1ae714a..a6fbdecf 100644
--- a/frontend/mobile-app/lib/features/pre_planting/presentation/pages/pre_planting_purchase_page.dart
+++ b/frontend/mobile-app/lib/features/pre_planting/presentation/pages/pre_planting_purchase_page.dart
@@ -6,6 +6,7 @@ import '../../../../core/di/injection_container.dart';
 import '../../../../core/services/pre_planting_service.dart';
 import '../../../../core/services/tree_pricing_service.dart';
 import '../../../../routes/route_paths.dart';
+import '../../../planting/presentation/widgets/password_verify_dialog.dart'; // [2026-03-05] 支付密码验证
 
 // ============================================
 // [2026-02-17] 预种计划购买页面
@@ -344,6 +345,19 @@ class _PrePlantingPurchasePageState
     final confirmed = await _showConfirmDialog();
     if (confirmed != true || !mounted) return;
 
+    // 第三步：验证支付密码 [2026-03-05]
+    final verified = await PasswordVerifyDialog.show(
+      context: context,
+      title: '验证支付密码',
+      subtitle: '为保障资金安全，请输入您的6位支付密码以确认预种',
+      hint: '请输入支付密码',
+      onVerify: (password) async {
+        final accountService = ref.read(accountServiceProvider);
+        return await accountService.verifyPaymentPassword(password);
+      },
+    );
+    if (verified != true || !mounted) return;
+
     setState(() => _isPurchasing = true);
 
     try {
diff --git a/frontend/mobile-app/lib/features/profile/presentation/pages/profile_page.dart b/frontend/mobile-app/lib/features/profile/presentation/pages/profile_page.dart
index 7ef885b5..f70277e7 100644
--- a/frontend/mobile-app/lib/features/profile/presentation/pages/profile_page.dart
+++ b/frontend/mobile-app/lib/features/profile/presentation/pages/profile_page.dart
@@ -1342,11 +1342,16 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
     context.push(RoutePaths.googleAuth);
   }
 
-  /// 修改密码
+  /// 修改登录密码
   void _goToChangePassword() {
     context.push(RoutePaths.changePassword);
   }
 
+  /// 支付密码设置/修改 [2026-03-05]
+  void _goToPaymentPassword() {
+    context.push(RoutePaths.paymentPassword);
+  }
+
   /// 绑定邮箱
   void _goToBindEmail() {
     context.push(RoutePaths.bindEmail);
@@ -4206,9 +4211,14 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
           // ),
           _buildSettingItem(
             icon: Icons.lock,
-            title: '修改登录密码',
+            title: '修改密码',
             onTap: _goToChangePassword,
           ),
+          _buildSettingItem(
+            icon: Icons.payment,
+            title: '支付密码',
+            onTap: _goToPaymentPassword,
+          ),
           _buildSettingItem(
             icon: Icons.email,
             title: '绑定邮箱',
diff --git a/frontend/mobile-app/lib/features/security/presentation/pages/change_payment_password_page.dart b/frontend/mobile-app/lib/features/security/presentation/pages/change_payment_password_page.dart
new file mode 100644
index 00000000..5ec834dd
--- /dev/null
+++ b/frontend/mobile-app/lib/features/security/presentation/pages/change_payment_password_page.dart
@@ -0,0 +1,487 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
+import '../../../../core/di/injection_container.dart';
+
+/// 支付密码设置/修改页面
+///
+/// - 未设置时：直接输入新密码（首次设置）
+/// - 已设置时：需验证旧密码后修改
+///
+/// 支付密码格式：6位纯数字
+class ChangePaymentPasswordPage extends ConsumerStatefulWidget {
+  const ChangePaymentPasswordPage({super.key});
+
+  @override
+  ConsumerState<ChangePaymentPasswordPage> createState() =>
+      _ChangePaymentPasswordPageState();
+}
+
+class _ChangePaymentPasswordPageState
+    extends ConsumerState<ChangePaymentPasswordPage> {
+  final TextEditingController _oldPasswordController = TextEditingController();
+  final TextEditingController _newPasswordController = TextEditingController();
+  final TextEditingController _confirmPasswordController =
+      TextEditingController();
+
+  bool _showOldPassword = false;
+  bool _showNewPassword = false;
+  bool _showConfirmPassword = false;
+  bool _isSubmitting = false;
+  bool _hasPaymentPassword = false;
+  bool _isLoading = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _loadStatus();
+  }
+
+  @override
+  void dispose() {
+    _oldPasswordController.dispose();
+    _newPasswordController.dispose();
+    _confirmPasswordController.dispose();
+    super.dispose();
+  }
+
+  Future<void> _loadStatus() async {
+    setState(() => _isLoading = true);
+    try {
+      final accountService = ref.read(accountServiceProvider);
+      final hasPassword = await accountService.isPaymentPasswordSet();
+      if (mounted) {
+        setState(() {
+          _hasPaymentPassword = hasPassword;
+          _isLoading = false;
+        });
+      }
+    } catch (e) {
+      if (mounted) {
+        setState(() {
+          _hasPaymentPassword = false;
+          _isLoading = false;
+        });
+      }
+    }
+  }
+
+  /// 校验支付密码格式：6位纯数字
+  String? _validatePassword(String password) {
+    if (password.length != 6) return '支付密码必须为6位数字';
+    if (!RegExp(r'^\d{6}$').hasMatch(password)) return '支付密码只能包含数字';
+    return null;
+  }
+
+  Future<void> _submit() async {
+    final oldPassword = _oldPasswordController.text;
+    final newPassword = _newPasswordController.text;
+    final confirmPassword = _confirmPasswordController.text;
+
+    if (_hasPaymentPassword && oldPassword.isEmpty) {
+      _showError('请输入当前支付密码');
+      return;
+    }
+    if (newPassword.isEmpty) {
+      _showError('请输入新支付密码');
+      return;
+    }
+    final formatError = _validatePassword(newPassword);
+    if (formatError != null) {
+      _showError(formatError);
+      return;
+    }
+    if (confirmPassword != newPassword) {
+      _showError('两次输入的支付密码不一致');
+      return;
+    }
+
+    setState(() => _isSubmitting = true);
+    try {
+      final accountService = ref.read(accountServiceProvider);
+      if (_hasPaymentPassword) {
+        await accountService.changePaymentPassword(
+          oldPassword: oldPassword,
+          newPassword: newPassword,
+        );
+      } else {
+        await accountService.setPaymentPassword(newPassword);
+      }
+
+      if (mounted) {
+        setState(() => _isSubmitting = false);
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text(_hasPaymentPassword ? '支付密码修改成功' : '支付密码设置成功'),
+            backgroundColor: const Color(0xFF4CAF50),
+          ),
+        );
+        context.pop(true);
+      }
+    } catch (e) {
+      if (mounted) {
+        setState(() => _isSubmitting = false);
+        _showError(
+            '操作失败: ${e.toString().replaceAll('Exception: ', '')}');
+      }
+    }
+  }
+
+  void _showError(String message) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(content: Text(message), backgroundColor: Colors.red),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: Colors.white,
+      body: Container(
+        width: double.infinity,
+        height: double.infinity,
+        decoration: const BoxDecoration(
+          gradient: LinearGradient(
+            begin: Alignment.topCenter,
+            end: Alignment.bottomCenter,
+            colors: [Color(0xFFFFF5E6), Color(0xFFFFE4B5)],
+          ),
+        ),
+        child: SafeArea(
+          child: Column(
+            children: [
+              _buildAppBar(),
+              Expanded(
+                child: _isLoading
+                    ? const Center(
+                        child: CircularProgressIndicator(
+                          valueColor: AlwaysStoppedAnimation<Color>(
+                              Color(0xFFD4AF37)),
+                        ),
+                      )
+                    : SingleChildScrollView(
+                        padding: const EdgeInsets.all(16),
+                        child: Column(
+                          crossAxisAlignment: CrossAxisAlignment.start,
+                          children: [
+                            _buildStatusCard(),
+                            const SizedBox(height: 24),
+                            _buildPasswordRequirements(),
+                            const SizedBox(height: 24),
+                            if (_hasPaymentPassword) ...[
+                              _buildPasswordInput(
+                                controller: _oldPasswordController,
+                                label: '当前支付密码',
+                                hint: '请输入当前6位支付密码',
+                                showPassword: _showOldPassword,
+                                onToggleVisibility: () => setState(
+                                    () => _showOldPassword = !_showOldPassword),
+                              ),
+                              const SizedBox(height: 16),
+                            ],
+                            _buildPasswordInput(
+                              controller: _newPasswordController,
+                              label: '新支付密码',
+                              hint: '请输入6位数字支付密码',
+                              showPassword: _showNewPassword,
+                              onToggleVisibility: () => setState(
+                                  () => _showNewPassword = !_showNewPassword),
+                            ),
+                            const SizedBox(height: 16),
+                            _buildPasswordInput(
+                              controller: _confirmPasswordController,
+                              label: '确认支付密码',
+                              hint: '请再次输入6位支付密码',
+                              showPassword: _showConfirmPassword,
+                              onToggleVisibility: () => setState(() =>
+                                  _showConfirmPassword = !_showConfirmPassword),
+                            ),
+                            const SizedBox(height: 32),
+                            _buildSubmitButton(),
+                          ],
+                        ),
+                      ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildAppBar() {
+    return Container(
+      height: 64,
+      padding: const EdgeInsets.only(top: 16, left: 16, right: 16),
+      child: Row(
+        children: [
+          GestureDetector(
+            onTap: () => context.pop(),
+            child: Container(
+              width: 48,
+              height: 48,
+              alignment: Alignment.center,
+              child: const Icon(Icons.arrow_back,
+                  size: 24, color: Color(0xFF5D4037)),
+            ),
+          ),
+          Expanded(
+            child: Text(
+              _hasPaymentPassword ? '修改支付密码' : '设置支付密码',
+              style: const TextStyle(
+                fontSize: 18,
+                fontFamily: 'Inter',
+                fontWeight: FontWeight.w500,
+                height: 1.25,
+                letterSpacing: -0.27,
+                color: Color(0xFF5D4037),
+              ),
+              textAlign: TextAlign.center,
+            ),
+          ),
+          const SizedBox(width: 48),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildStatusCard() {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: const Color(0x80FFFFFF),
+        borderRadius: BorderRadius.circular(12),
+        border: Border.all(color: const Color(0x33D4AF37), width: 1),
+      ),
+      child: Row(
+        children: [
+          Container(
+            width: 48,
+            height: 48,
+            decoration: BoxDecoration(
+              color: _hasPaymentPassword
+                  ? const Color(0xFF4CAF50).withValues(alpha: 0.1)
+                  : const Color(0xFFFF9800).withValues(alpha: 0.1),
+              borderRadius: BorderRadius.circular(24),
+            ),
+            child: Icon(
+              _hasPaymentPassword ? Icons.payment : Icons.payment_outlined,
+              color: _hasPaymentPassword
+                  ? const Color(0xFF4CAF50)
+                  : const Color(0xFFFF9800),
+              size: 24,
+            ),
+          ),
+          const SizedBox(width: 16),
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  _hasPaymentPassword ? '已设置支付密码' : '未设置支付密码',
+                  style: TextStyle(
+                    fontSize: 18,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w600,
+                    color: _hasPaymentPassword
+                        ? const Color(0xFF4CAF50)
+                        : const Color(0xFFFF9800),
+                  ),
+                ),
+                const SizedBox(height: 4),
+                Text(
+                  _hasPaymentPassword
+                      ? '认种、预种等支付操作需要验证支付密码'
+                      : '设置后，认种和预种时需输入支付密码确认',
+                  style: const TextStyle(
+                    fontSize: 14,
+                    fontFamily: 'Inter',
+                    color: Color(0xFF745D43),
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildPasswordRequirements() {
+    return Container(
+      width: double.infinity,
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: const Color(0xFFFFF5E6),
+        borderRadius: BorderRadius.circular(12),
+        border: Border.all(color: const Color(0x33D4AF37), width: 1),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          const Row(
+            children: [
+              Icon(Icons.info_outline, size: 20, color: Color(0xFF8B5A2B)),
+              SizedBox(width: 8),
+              Text(
+                '支付密码要求',
+                style: TextStyle(
+                  fontSize: 16,
+                  fontFamily: 'Inter',
+                  fontWeight: FontWeight.w600,
+                  color: Color(0xFF5D4037),
+                ),
+              ),
+            ],
+          ),
+          const SizedBox(height: 12),
+          _buildRequirementItem('必须为 6 位纯数字'),
+          _buildRequirementItem('与登录密码相互独立'),
+          _buildRequirementItem('用于认种、预种等支付场景的二次验证'),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildRequirementItem(String text) {
+    return Padding(
+      padding: const EdgeInsets.only(top: 8),
+      child: Row(
+        children: [
+          const Icon(Icons.check_circle_outline,
+              size: 16, color: Color(0xFFD4AF37)),
+          const SizedBox(width: 8),
+          Expanded(
+            child: Text(
+              text,
+              style: const TextStyle(
+                fontSize: 14,
+                fontFamily: 'Inter',
+                color: Color(0xFF745D43),
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildPasswordInput({
+    required TextEditingController controller,
+    required String label,
+    required String hint,
+    required bool showPassword,
+    required VoidCallback onToggleVisibility,
+  }) {
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Text(
+          label,
+          style: const TextStyle(
+            fontSize: 16,
+            fontFamily: 'Inter',
+            fontWeight: FontWeight.w500,
+            color: Color(0xFF5D4037),
+          ),
+        ),
+        const SizedBox(height: 8),
+        Container(
+          width: double.infinity,
+          height: 54,
+          decoration: BoxDecoration(
+            color: const Color(0x80FFFFFF),
+            borderRadius: BorderRadius.circular(12),
+            border: Border.all(color: const Color(0x80FFFFFF), width: 1),
+            boxShadow: const [
+              BoxShadow(
+                color: Color(0x0D000000),
+                blurRadius: 2,
+                offset: Offset(0, 1),
+              ),
+            ],
+          ),
+          child: TextField(
+            controller: controller,
+            obscureText: !showPassword,
+            keyboardType: TextInputType.number,
+            maxLength: 6,
+            style: const TextStyle(
+              fontSize: 16,
+              fontFamily: 'Inter',
+              height: 1.19,
+              color: Color(0xFF5D4037),
+            ),
+            decoration: InputDecoration(
+              contentPadding:
+                  const EdgeInsets.symmetric(horizontal: 16, vertical: 15),
+              border: InputBorder.none,
+              counterText: '',
+              hintText: hint,
+              hintStyle: const TextStyle(
+                fontSize: 16,
+                fontFamily: 'Inter',
+                height: 1.19,
+                color: Color(0x995D4037),
+              ),
+              suffixIcon: GestureDetector(
+                onTap: onToggleVisibility,
+                child: Icon(
+                  showPassword ? Icons.visibility_off : Icons.visibility,
+                  color: const Color(0xFF8B5A2B),
+                  size: 20,
+                ),
+              ),
+            ),
+          ),
+        ),
+      ],
+    );
+  }
+
+  Widget _buildSubmitButton() {
+    return GestureDetector(
+      onTap: _isSubmitting ? null : _submit,
+      child: Container(
+        width: double.infinity,
+        height: 56,
+        decoration: BoxDecoration(
+          color: _isSubmitting
+              ? const Color(0xFFD4AF37).withValues(alpha: 0.5)
+              : const Color(0xFFD4AF37),
+          borderRadius: BorderRadius.circular(12),
+          boxShadow: const [
+            BoxShadow(
+              color: Color(0x4DD4AF37),
+              blurRadius: 14,
+              offset: Offset(0, 4),
+            ),
+          ],
+        ),
+        child: Center(
+          child: _isSubmitting
+              ? const SizedBox(
+                  width: 24,
+                  height: 24,
+                  child: CircularProgressIndicator(
+                    strokeWidth: 2,
+                    valueColor: AlwaysStoppedAnimation<Color>(Colors.white),
+                  ),
+                )
+              : Text(
+                  _hasPaymentPassword ? '修改支付密码' : '设置支付密码',
+                  style: const TextStyle(
+                    fontSize: 16,
+                    fontFamily: 'Inter',
+                    fontWeight: FontWeight.w700,
+                    height: 1.5,
+                    letterSpacing: 0.24,
+                    color: Colors.white,
+                  ),
+                ),
+        ),
+      ),
+    );
+  }
+}
diff --git a/frontend/mobile-app/lib/routes/app_router.dart b/frontend/mobile-app/lib/routes/app_router.dart
index 3bc7e4ef..3ad4afa7 100644
--- a/frontend/mobile-app/lib/routes/app_router.dart
+++ b/frontend/mobile-app/lib/routes/app_router.dart
@@ -27,6 +27,7 @@ import '../features/planting/presentation/pages/planting_quantity_page.dart';
 import '../features/planting/presentation/pages/planting_location_page.dart';
 import '../features/security/presentation/pages/google_auth_page.dart';
 import '../features/security/presentation/pages/change_password_page.dart';
+import '../features/security/presentation/pages/change_payment_password_page.dart'; // [2026-03-05] 支付密码页
 import '../features/security/presentation/pages/bind_email_page.dart';
 import '../features/authorization/presentation/pages/authorization_apply_page.dart';
 import '../features/withdraw/presentation/pages/withdraw_usdt_page.dart';
@@ -341,6 +342,13 @@ final appRouterProvider = Provider<GoRouter>((ref) {
         builder: (context, state) => const ChangePasswordPage(),
       ),
 
+      // Payment Password Page (支付密码设置/修改) [2026-03-05]
+      GoRoute(
+        path: RoutePaths.paymentPassword,
+        name: RouteNames.paymentPassword,
+        builder: (context, state) => const ChangePaymentPasswordPage(),
+      ),
+
       // Bind Email Page (绑定邮箱)
       GoRoute(
         path: RoutePaths.bindEmail,
diff --git a/frontend/mobile-app/lib/routes/route_names.dart b/frontend/mobile-app/lib/routes/route_names.dart
index d1517ffa..a518effe 100644
--- a/frontend/mobile-app/lib/routes/route_names.dart
+++ b/frontend/mobile-app/lib/routes/route_names.dart
@@ -35,6 +35,7 @@ class RouteNames {
   static const plantingLocation = 'planting-location';
   static const googleAuth = 'google-auth';
   static const changePassword = 'change-password';
+  static const paymentPassword = 'payment-password'; // [2026-03-05] 支付密码
   static const bindEmail = 'bind-email';
   static const authorizationApply = 'authorization-apply';
   static const transactionHistory = 'transaction-history';
diff --git a/frontend/mobile-app/lib/routes/route_paths.dart b/frontend/mobile-app/lib/routes/route_paths.dart
index 942f5af1..7d2ae885 100644
--- a/frontend/mobile-app/lib/routes/route_paths.dart
+++ b/frontend/mobile-app/lib/routes/route_paths.dart
@@ -35,6 +35,7 @@ class RoutePaths {
   static const plantingLocation = '/planting/location';
   static const googleAuth = '/security/google-auth';
   static const changePassword = '/security/password';
+  static const paymentPassword = '/security/payment-password'; // [2026-03-05] 支付密码设置/修改
   static const bindEmail = '/security/email';
   static const authorizationApply = '/authorization/apply';
   static const transactionHistory = '/trading/history';