diff --git a/backend/internal/handler/admin/user_handler.go b/backend/internal/handler/admin/user_handler.go
index 38cc8acd..9a5a691f 100644
--- a/backend/internal/handler/admin/user_handler.go
+++ b/backend/internal/handler/admin/user_handler.go
@@ -84,9 +84,9 @@ func (h *UserHandler) List(c *gin.Context) {
 		return
 	}
 
-	out := make([]dto.User, 0, len(users))
+	out := make([]dto.AdminUser, 0, len(users))
 	for i := range users {
-		out = append(out, *dto.UserFromService(&users[i]))
+		out = append(out, *dto.UserFromServiceAdmin(&users[i]))
 	}
 	response.Paginated(c, out, total, page, pageSize)
 }
@@ -129,7 +129,7 @@ func (h *UserHandler) GetByID(c *gin.Context) {
 		return
 	}
 
-	response.Success(c, dto.UserFromService(user))
+	response.Success(c, dto.UserFromServiceAdmin(user))
 }
 
 // Create handles creating a new user
@@ -155,7 +155,7 @@ func (h *UserHandler) Create(c *gin.Context) {
 		return
 	}
 
-	response.Success(c, dto.UserFromService(user))
+	response.Success(c, dto.UserFromServiceAdmin(user))
 }
 
 // Update handles updating a user
@@ -189,7 +189,7 @@ func (h *UserHandler) Update(c *gin.Context) {
 		return
 	}
 
-	response.Success(c, dto.UserFromService(user))
+	response.Success(c, dto.UserFromServiceAdmin(user))
 }
 
 // Delete handles deleting a user
@@ -231,7 +231,7 @@ func (h *UserHandler) UpdateBalance(c *gin.Context) {
 		return
 	}
 
-	response.Success(c, dto.UserFromService(user))
+	response.Success(c, dto.UserFromServiceAdmin(user))
 }
 
 // GetUserAPIKeys handles getting user's API keys
diff --git a/backend/internal/handler/dto/mappers.go b/backend/internal/handler/dto/mappers.go
index 3a3a18b2..e768b188 100644
--- a/backend/internal/handler/dto/mappers.go
+++ b/backend/internal/handler/dto/mappers.go
@@ -15,7 +15,6 @@ func UserFromServiceShallow(u *service.User) *User {
 		ID:            u.ID,
 		Email:         u.Email,
 		Username:      u.Username,
-		Notes:         u.Notes,
 		Role:          u.Role,
 		Balance:       u.Balance,
 		Concurrency:   u.Concurrency,
@@ -48,6 +47,22 @@ func UserFromService(u *service.User) *User {
 	return out
 }
 
+// UserFromServiceAdmin converts a service User to DTO for admin users.
+// It includes notes - user-facing endpoints must not use this.
+func UserFromServiceAdmin(u *service.User) *AdminUser {
+	if u == nil {
+		return nil
+	}
+	base := UserFromService(u)
+	if base == nil {
+		return nil
+	}
+	return &AdminUser{
+		User:  *base,
+		Notes: u.Notes,
+	}
+}
+
 func APIKeyFromService(k *service.APIKey) *APIKey {
 	if k == nil {
 		return nil
diff --git a/backend/internal/handler/dto/types.go b/backend/internal/handler/dto/types.go
index 60e7c9bf..649cc036 100644
--- a/backend/internal/handler/dto/types.go
+++ b/backend/internal/handler/dto/types.go
@@ -6,7 +6,6 @@ type User struct {
 	ID            int64     `json:"id"`
 	Email         string    `json:"email"`
 	Username      string    `json:"username"`
-	Notes         string    `json:"notes"`
 	Role          string    `json:"role"`
 	Balance       float64   `json:"balance"`
 	Concurrency   int       `json:"concurrency"`
@@ -19,6 +18,14 @@ type User struct {
 	Subscriptions []UserSubscription `json:"subscriptions,omitempty"`
 }
 
+// AdminUser 是管理员接口使用的 user DTO（包含敏感/内部字段）。
+// 注意：普通用户接口不得返回 notes 等管理员备注信息。
+type AdminUser struct {
+	User
+
+	Notes string `json:"notes"`
+}
+
 type APIKey struct {
 	ID          int64     `json:"id"`
 	UserID      int64     `json:"user_id"`
diff --git a/backend/internal/handler/user_handler.go b/backend/internal/handler/user_handler.go
index d968951c..35862f1c 100644
--- a/backend/internal/handler/user_handler.go
+++ b/backend/internal/handler/user_handler.go
@@ -47,9 +47,6 @@ func (h *UserHandler) GetProfile(c *gin.Context) {
 		return
 	}
 
-	// 清空notes字段，普通用户不应看到备注
-	userData.Notes = ""
-
 	response.Success(c, dto.UserFromService(userData))
 }
 
@@ -105,8 +102,5 @@ func (h *UserHandler) UpdateProfile(c *gin.Context) {
 		return
 	}
 
-	// 清空notes字段，普通用户不应看到备注
-	updatedUser.Notes = ""
-
 	response.Success(c, dto.UserFromService(updatedUser))
 }
diff --git a/backend/internal/server/api_contract_test.go b/backend/internal/server/api_contract_test.go
index 814668d3..c4cbc038 100644
--- a/backend/internal/server/api_contract_test.go
+++ b/backend/internal/server/api_contract_test.go
@@ -51,7 +51,6 @@ func TestAPIContracts(t *testing.T) {
 					"id": 1,
 					"email": "alice@example.com",
 					"username": "alice",
-					"notes": "hello",
 					"role": "user",
 					"balance": 12.5,
 					"concurrency": 5,
diff --git a/frontend/src/api/admin/users.ts b/frontend/src/api/admin/users.ts
index 44963cf9..734e3ac7 100644
--- a/frontend/src/api/admin/users.ts
+++ b/frontend/src/api/admin/users.ts
@@ -4,7 +4,7 @@
  */
 
 import { apiClient } from '../client'
-import type { User, UpdateUserRequest, PaginatedResponse } from '@/types'
+import type { AdminUser, UpdateUserRequest, PaginatedResponse } from '@/types'
 
 /**
  * List all users with pagination
@@ -26,7 +26,7 @@ export async function list(
   options?: {
     signal?: AbortSignal
   }
-): Promise<PaginatedResponse<User>> {
+): Promise<PaginatedResponse<AdminUser>> {
   // Build params with attribute filters in attr[id]=value format
   const params: Record<string, any> = {
     page,
@@ -44,8 +44,7 @@ export async function list(
       }
     }
   }
-
-  const { data } = await apiClient.get<PaginatedResponse<User>>('/admin/users', {
+  const { data } = await apiClient.get<PaginatedResponse<AdminUser>>('/admin/users', {
     params,
     signal: options?.signal
   })
@@ -57,8 +56,8 @@ export async function list(
  * @param id - User ID
  * @returns User details
  */
-export async function getById(id: number): Promise<User> {
-  const { data } = await apiClient.get<User>(`/admin/users/${id}`)
+export async function getById(id: number): Promise<AdminUser> {
+  const { data } = await apiClient.get<AdminUser>(`/admin/users/${id}`)
   return data
 }
 
@@ -73,8 +72,8 @@ export async function create(userData: {
   balance?: number
   concurrency?: number
   allowed_groups?: number[] | null
-}): Promise<User> {
-  const { data } = await apiClient.post<User>('/admin/users', userData)
+}): Promise<AdminUser> {
+  const { data } = await apiClient.post<AdminUser>('/admin/users', userData)
   return data
 }
 
@@ -84,8 +83,8 @@ export async function create(userData: {
  * @param updates - Fields to update
  * @returns Updated user
  */
-export async function update(id: number, updates: UpdateUserRequest): Promise<User> {
-  const { data } = await apiClient.put<User>(`/admin/users/${id}`, updates)
+export async function update(id: number, updates: UpdateUserRequest): Promise<AdminUser> {
+  const { data } = await apiClient.put<AdminUser>(`/admin/users/${id}`, updates)
   return data
 }
 
@@ -112,8 +111,8 @@ export async function updateBalance(
   balance: number,
   operation: 'set' | 'add' | 'subtract' = 'set',
   notes?: string
-): Promise<User> {
-  const { data } = await apiClient.post<User>(`/admin/users/${id}/balance`, {
+): Promise<AdminUser> {
+  const { data } = await apiClient.post<AdminUser>(`/admin/users/${id}/balance`, {
     balance,
     operation,
     notes: notes || ''
@@ -127,7 +126,7 @@ export async function updateBalance(
  * @param concurrency - New concurrency limit
  * @returns Updated user
  */
-export async function updateConcurrency(id: number, concurrency: number): Promise<User> {
+export async function updateConcurrency(id: number, concurrency: number): Promise<AdminUser> {
   return update(id, { concurrency })
 }
 
@@ -137,7 +136,7 @@ export async function updateConcurrency(id: number, concurrency: number): Promis
  * @param status - New status
  * @returns Updated user
  */
-export async function toggleStatus(id: number, status: 'active' | 'disabled'): Promise<User> {
+export async function toggleStatus(id: number, status: 'active' | 'disabled'): Promise<AdminUser> {
   return update(id, { status })
 }
 
diff --git a/frontend/src/components/admin/user/UserAllowedGroupsModal.vue b/frontend/src/components/admin/user/UserAllowedGroupsModal.vue
index c1783fd2..825d2be5 100644
--- a/frontend/src/components/admin/user/UserAllowedGroupsModal.vue
+++ b/frontend/src/components/admin/user/UserAllowedGroupsModal.vue
@@ -39,10 +39,10 @@ import { ref, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores/app'
 import { adminAPI } from '@/api/admin'
-import type { User, Group } from '@/types'
+import type { AdminUser, Group } from '@/types'
 import BaseDialog from '@/components/common/BaseDialog.vue'
 
-const props = defineProps<{ show: boolean, user: User | null }>()
+const props = defineProps<{ show: boolean, user: AdminUser | null }>()
 const emit = defineEmits(['close', 'success']); const { t } = useI18n(); const appStore = useAppStore()
 
 const groups = ref<Group[]>([]); const selectedIds = ref<number[]>([]); const loading = ref(false); const submitting = ref(false)
@@ -56,4 +56,4 @@ const handleSave = async () => {
     appStore.showSuccess(t('admin.users.allowedGroupsUpdated')); emit('success'); emit('close')
   } catch (error) { console.error('Failed to update allowed groups:', error) } finally { submitting.value = false }
 }
-</script>
\ No newline at end of file
+</script>
diff --git a/frontend/src/components/admin/user/UserApiKeysModal.vue b/frontend/src/components/admin/user/UserApiKeysModal.vue
index ef098ba1..c2159ff4 100644
--- a/frontend/src/components/admin/user/UserApiKeysModal.vue
+++ b/frontend/src/components/admin/user/UserApiKeysModal.vue
@@ -32,10 +32,10 @@ import { ref, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { adminAPI } from '@/api/admin'
 import { formatDateTime } from '@/utils/format'
-import type { User, ApiKey } from '@/types'
+import type { AdminUser, ApiKey } from '@/types'
 import BaseDialog from '@/components/common/BaseDialog.vue'
 
-const props = defineProps<{ show: boolean, user: User | null }>()
+const props = defineProps<{ show: boolean, user: AdminUser | null }>()
 defineEmits(['close']); const { t } = useI18n()
 const apiKeys = ref<ApiKey[]>([]); const loading = ref(false)
 
@@ -44,4 +44,4 @@ const load = async () => {
   if (!props.user) return; loading.value = true
   try { const res = await adminAPI.users.getUserApiKeys(props.user.id); apiKeys.value = res.items || [] } catch (error) { console.error('Failed to load API keys:', error) } finally { loading.value = false }
 }
-</script>
\ No newline at end of file
+</script>
diff --git a/frontend/src/components/admin/user/UserBalanceModal.vue b/frontend/src/components/admin/user/UserBalanceModal.vue
index c669c2a5..143350bf 100644
--- a/frontend/src/components/admin/user/UserBalanceModal.vue
+++ b/frontend/src/components/admin/user/UserBalanceModal.vue
@@ -29,10 +29,10 @@ import { reactive, ref, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores/app'
 import { adminAPI } from '@/api/admin'
-import type { User } from '@/types'
+import type { AdminUser } from '@/types'
 import BaseDialog from '@/components/common/BaseDialog.vue'
 
-const props = defineProps<{ show: boolean, user: User | null, operation: 'add' | 'subtract' }>()
+const props = defineProps<{ show: boolean, user: AdminUser | null, operation: 'add' | 'subtract' }>()
 const emit = defineEmits(['close', 'success']); const { t } = useI18n(); const appStore = useAppStore()
 
 const submitting = ref(false); const form = reactive({ amount: 0, notes: '' })
diff --git a/frontend/src/components/admin/user/UserEditModal.vue b/frontend/src/components/admin/user/UserEditModal.vue
index 2c4b117a..70ebd2d3 100644
--- a/frontend/src/components/admin/user/UserEditModal.vue
+++ b/frontend/src/components/admin/user/UserEditModal.vue
@@ -56,12 +56,12 @@ import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores/app'
 import { useClipboard } from '@/composables/useClipboard'
 import { adminAPI } from '@/api/admin'
-import type { User, UserAttributeValuesMap } from '@/types'
+import type { AdminUser, UserAttributeValuesMap } from '@/types'
 import BaseDialog from '@/components/common/BaseDialog.vue'
 import UserAttributeForm from '@/components/user/UserAttributeForm.vue'
 import Icon from '@/components/icons/Icon.vue'
 
-const props = defineProps<{ show: boolean, user: User | null }>()
+const props = defineProps<{ show: boolean, user: AdminUser | null }>()
 const emit = defineEmits(['close', 'success'])
 const { t } = useI18n(); const appStore = useAppStore(); const { copyToClipboard } = useClipboard()
 
diff --git a/frontend/src/types/index.ts b/frontend/src/types/index.ts
index fbf41898..eef022d9 100644
--- a/frontend/src/types/index.ts
+++ b/frontend/src/types/index.ts
@@ -27,7 +27,6 @@ export interface FetchOptions {
 export interface User {
   id: number
   username: string
-  notes: string
   email: string
   role: 'admin' | 'user' // User role for authorization
   balance: number // User balance for API usage
@@ -39,6 +38,11 @@ export interface User {
   updated_at: string
 }
 
+export interface AdminUser extends User {
+  // 管理员备注（普通用户接口不返回）
+  notes: string
+}
+
 export interface LoginRequest {
   email: string
   password: string
diff --git a/frontend/src/views/admin/UsersView.vue b/frontend/src/views/admin/UsersView.vue
index 4ce839f1..2a73a977 100644
--- a/frontend/src/views/admin/UsersView.vue
+++ b/frontend/src/views/admin/UsersView.vue
@@ -492,7 +492,7 @@ import Icon from '@/components/icons/Icon.vue'
 
 const { t } = useI18n()
 import { adminAPI } from '@/api/admin'
-import type { User, UserAttributeDefinition } from '@/types'
+import type { AdminUser, UserAttributeDefinition } from '@/types'
 import type { BatchUserUsageStats } from '@/api/admin/dashboard'
 import type { Column } from '@/components/common/types'
 import AppLayout from '@/components/layout/AppLayout.vue'
@@ -637,7 +637,7 @@ const columns = computed<Column[]>(() =>
   )
 )
 
-const users = ref<User[]>([])
+const users = ref<AdminUser[]>([])
 const loading = ref(false)
 const searchQuery = ref('')
 
@@ -736,16 +736,16 @@ const showEditModal = ref(false)
 const showDeleteDialog = ref(false)
 const showApiKeysModal = ref(false)
 const showAttributesModal = ref(false)
-const editingUser = ref<User | null>(null)
-const deletingUser = ref<User | null>(null)
-const viewingUser = ref<User | null>(null)
+const editingUser = ref<AdminUser | null>(null)
+const deletingUser = ref<AdminUser | null>(null)
+const viewingUser = ref<AdminUser | null>(null)
 let abortController: AbortController | null = null
 
 // Action Menu State
 const activeMenuId = ref<number | null>(null)
 const menuPosition = ref<{ top: number; left: number } | null>(null)
 
-const openActionMenu = (user: User, e: MouseEvent) => {
+const openActionMenu = (user: AdminUser, e: MouseEvent) => {
   if (activeMenuId.value === user.id) {
     closeActionMenu()
   } else {
@@ -821,11 +821,11 @@ const handleClickOutside = (event: MouseEvent) => {
 
 // Allowed groups modal state
 const showAllowedGroupsModal = ref(false)
-const allowedGroupsUser = ref<User | null>(null)
+const allowedGroupsUser = ref<AdminUser | null>(null)
 
 // Balance (Deposit/Withdraw) modal state
 const showBalanceModal = ref(false)
-const balanceUser = ref<User | null>(null)
+const balanceUser = ref<AdminUser | null>(null)
 const balanceOperation = ref<'add' | 'subtract'>('add')
 
 // 计算剩余天数
@@ -998,7 +998,7 @@ const applyFilter = () => {
   loadUsers()
 }
 
-const handleEdit = (user: User) => {
+const handleEdit = (user: AdminUser) => {
   editingUser.value = user
   showEditModal.value = true
 }
@@ -1008,7 +1008,7 @@ const closeEditModal = () => {
   editingUser.value = null
 }
 
-const handleToggleStatus = async (user: User) => {
+const handleToggleStatus = async (user: AdminUser) => {
   const newStatus = user.status === 'active' ? 'disabled' : 'active'
   try {
     await adminAPI.users.toggleStatus(user.id, newStatus)
@@ -1022,7 +1022,7 @@ const handleToggleStatus = async (user: User) => {
   }
 }
 
-const handleViewApiKeys = (user: User) => {
+const handleViewApiKeys = (user: AdminUser) => {
   viewingUser.value = user
   showApiKeysModal.value = true
 }
@@ -1032,7 +1032,7 @@ const closeApiKeysModal = () => {
   viewingUser.value = null
 }
 
-const handleAllowedGroups = (user: User) => {
+const handleAllowedGroups = (user: AdminUser) => {
   allowedGroupsUser.value = user
   showAllowedGroupsModal.value = true
 }
@@ -1042,7 +1042,7 @@ const closeAllowedGroupsModal = () => {
   allowedGroupsUser.value = null
 }
 
-const handleDelete = (user: User) => {
+const handleDelete = (user: AdminUser) => {
   deletingUser.value = user
   showDeleteDialog.value = true
 }
@@ -1061,13 +1061,13 @@ const confirmDelete = async () => {
   }
 }
 
-const handleDeposit = (user: User) => {
+const handleDeposit = (user: AdminUser) => {
   balanceUser.value = user
   balanceOperation.value = 'add'
   showBalanceModal.value = true
 }
 
-const handleWithdraw = (user: User) => {
+const handleWithdraw = (user: AdminUser) => {
   balanceUser.value = user
   balanceOperation.value = 'subtract'
   showBalanceModal.value = true