diff --git a/lib/core/network/api_exception.dart b/lib/core/network/api_exception.dart
index 3e3604e..de6fe78 100644
--- a/lib/core/network/api_exception.dart
+++ b/lib/core/network/api_exception.dart
@@ -19,6 +19,9 @@ abstract final class ApiCodes {
 
   /// 手机号重复。
   static const phoneTaken = 40901;
+
+  /// 登录失败次数过多，账号临时锁定（HTTP 423，见 openapi.yaml）。
+  static const loginLocked = 42300;
 }
 
 /// API 调用的类型化异常。页面按类型映射为三层错误呈现
diff --git a/lib/features/auth/login_page.dart b/lib/features/auth/login_page.dart
index a1b89e3..cb1e623 100644
--- a/lib/features/auth/login_page.dart
+++ b/lib/features/auth/login_page.dart
@@ -110,9 +110,11 @@ class _LoginPageState extends State<LoginPage> {
       // 认证状态机随 saveSession 切换，根路由 300ms fade 进主壳。
     } on ApiBusinessException catch (error) {
       if (!mounted) return;
-      _showFormError(
-        error.code == ApiCodes.badCredentials ? '用户名或密码错误' : '登录失败，请稍后重试',
-      );
+      _showFormError(switch (error.code) {
+        ApiCodes.badCredentials => '用户名或密码错误',
+        ApiCodes.loginLocked => '尝试次数过多，账号已临时锁定，请稍后再试',
+        _ => '登录失败，请稍后重试',
+      });
     } on ApiRateLimitException {
       if (!mounted) return;
       _showFormError('尝试次数过多，请稍后再试');