diff --git a/frontend/src/i18n/__tests__/openaiFastPolicyLocales.spec.ts b/frontend/src/i18n/__tests__/openaiFastPolicyLocales.spec.ts
new file mode 100644
index 0000000000..7fd550c1ad
--- /dev/null
+++ b/frontend/src/i18n/__tests__/openaiFastPolicyLocales.spec.ts
@@ -0,0 +1,30 @@
+import { describe, expect, it } from 'vitest'
+
+import en from '../locales/en'
+import zh from '../locales/zh'
+
+describe('OpenAI Fast/Flex policy locale keys', () => {
+  it('exposes user scope copy at the runtime zh path', () => {
+    expect(zh.admin.settings.openaiFastPolicy).toMatchObject({
+      userIds: '指定用户',
+      userIdsHint: '输入任意邮箱关键词进行模糊搜索。留空表示对全部 Sub2API 用户生效；选中用户的 API Key 请求优先匹配用户规则。',
+      userSearchPlaceholder: '输入用户邮箱搜索',
+      userSearchEmpty: '未找到匹配用户',
+      userDeleted: '（已删除）',
+      userIdFallback: '用户 #{id}',
+      removeUser: '移除用户'
+    })
+  })
+
+  it('exposes user scope copy at the runtime en path', () => {
+    expect(en.admin.settings.openaiFastPolicy).toMatchObject({
+      userIds: 'Specific users',
+      userIdsHint: 'Type any part of a user email to search. Leave empty to apply to all Sub2API users. Selected users match requests from their API keys and take precedence over global rules.',
+      userSearchPlaceholder: 'Search by user email',
+      userSearchEmpty: 'No matching users found',
+      userDeleted: '(deleted)',
+      userIdFallback: 'User #{id}',
+      removeUser: 'Remove user'
+    })
+  })
+})
diff --git a/frontend/src/i18n/locales/en/admin/settings.ts b/frontend/src/i18n/locales/en/admin/settings.ts
index 37dc8aa1c8..e08be9f591 100644
--- a/frontend/src/i18n/locales/en/admin/settings.ts
+++ b/frontend/src/i18n/locales/en/admin/settings.ts
@@ -979,11 +979,6 @@ export default {
         scopeOAuth: 'OAuth only',
         scopeAPIKey: 'API Key only',
         scopeBedrock: 'Bedrock only',
-        userIds: 'Specific user IDs',
-        userIdsHint: 'Leave empty to apply to all Sub2API users. Specified users match requests from their API keys and take precedence over global rules.',
-        userIdPlaceholder: 'e.g., 1001',
-        addUserId: 'Add user ID',
-        removeUserId: 'Remove user ID',
         errorMessage: 'Error message',
         errorMessagePlaceholder: 'Custom error message when blocked',
         errorMessageHint: 'Leave empty for default message',
@@ -1024,6 +1019,13 @@ export default {
         scopeOAuth: 'OAuth only',
         scopeAPIKey: 'API Key only',
         scopeBedrock: 'Bedrock only',
+        userIds: 'Specific users',
+        userIdsHint: 'Type any part of a user email to search. Leave empty to apply to all Sub2API users. Selected users match requests from their API keys and take precedence over global rules.',
+        userSearchPlaceholder: 'Search by user email',
+        userSearchEmpty: 'No matching users found',
+        userDeleted: '(deleted)',
+        userIdFallback: 'User #{id}',
+        removeUser: 'Remove user',
         errorMessage: 'Error message',
         errorMessagePlaceholder: 'Custom error message when blocked',
         errorMessageHint: 'Leave empty for the default message.',
diff --git a/frontend/src/i18n/locales/zh/admin/settings.ts b/frontend/src/i18n/locales/zh/admin/settings.ts
index 5c0d874b57..08c0dbcd53 100644
--- a/frontend/src/i18n/locales/zh/admin/settings.ts
+++ b/frontend/src/i18n/locales/zh/admin/settings.ts
@@ -974,11 +974,6 @@ export default {
         scopeOAuth: '仅 OAuth 账号',
         scopeAPIKey: '仅 API Key 账号',
         scopeBedrock: '仅 Bedrock 账号',
-        userIds: '指定用户 ID',
-        userIdsHint: '留空表示对全部 Sub2API 用户生效。指定后仅匹配这些用户的 API Key 请求，且优先于全局规则。',
-        userIdPlaceholder: '例如: 1001',
-        addUserId: '添加用户 ID',
-        removeUserId: '移除用户 ID',
         errorMessage: '错误消息',
         errorMessagePlaceholder: '拦截时返回的自定义错误消息',
         errorMessageHint: '留空则使用默认错误消息',
@@ -1019,6 +1014,13 @@ export default {
         scopeOAuth: '仅 OAuth 账号',
         scopeAPIKey: '仅 API Key 账号',
         scopeBedrock: '仅 Bedrock 账号',
+        userIds: '指定用户',
+        userIdsHint: '输入任意邮箱关键词进行模糊搜索。留空表示对全部 Sub2API 用户生效；选中用户的 API Key 请求优先匹配用户规则。',
+        userSearchPlaceholder: '输入用户邮箱搜索',
+        userSearchEmpty: '未找到匹配用户',
+        userDeleted: '（已删除）',
+        userIdFallback: '用户 #{id}',
+        removeUser: '移除用户',
         errorMessage: '错误消息',
         errorMessagePlaceholder: '拦截时返回的自定义错误消息',
         errorMessageHint: '留空则使用默认错误消息。',
diff --git a/frontend/src/views/admin/SettingsView.vue b/frontend/src/views/admin/SettingsView.vue
index a87cea9060..26253c7eb8 100644
--- a/frontend/src/views/admin/SettingsView.vue
+++ b/frontend/src/views/admin/SettingsView.vue
@@ -1199,60 +1199,10 @@
                   <p class="mb-2 text-xs text-gray-400 dark:text-gray-500">
                     {{ t("admin.settings.openaiFastPolicy.userIdsHint") }}
                   </p>
-                  <div
-                    v-for="(_, userIDIndex) in rule.user_ids || []"
-                    :key="userIDIndex"
-                    class="mb-1.5 flex items-center gap-2"
-                  >
-                    <input
-                      v-model.number="rule.user_ids![userIDIndex]"
-                      type="number"
-                      min="1"
-                      step="1"
-                      class="input input-sm flex-1"
-                      :placeholder="t('admin.settings.openaiFastPolicy.userIdPlaceholder')"
-                    />
-                    <button
-                      type="button"
-                      @click="removeOpenAIFastPolicyUserID(rule, userIDIndex)"
-                      class="shrink-0 rounded p-1 text-red-400 transition-colors hover:bg-red-50 hover:text-red-600 dark:hover:bg-red-900/20"
-                      :title="t('admin.settings.openaiFastPolicy.removeUserId')"
-                    >
-                      <svg
-                        class="h-4 w-4"
-                        fill="none"
-                        viewBox="0 0 24 24"
-                        stroke="currentColor"
-                        stroke-width="2"
-                      >
-                        <path
-                          stroke-linecap="round"
-                          stroke-linejoin="round"
-                          d="M6 18L18 6M6 6l12 12"
-                        />
-                      </svg>
-                    </button>
-                  </div>
-                  <button
-                    type="button"
-                    @click="addOpenAIFastPolicyUserID(rule)"
-                    class="mb-2 inline-flex items-center gap-1 text-xs text-primary-600 transition-colors hover:text-primary-700 dark:text-primary-400 dark:hover:text-primary-300"
-                  >
-                    <svg
-                      class="h-3.5 w-3.5"
-                      fill="none"
-                      viewBox="0 0 24 24"
-                      stroke="currentColor"
-                      stroke-width="2"
-                    >
-                      <path
-                        stroke-linecap="round"
-                        stroke-linejoin="round"
-                        d="M12 4v16m8-8H4"
-                      />
-                    </svg>
-                    {{ t("admin.settings.openaiFastPolicy.addUserId") }}
-                  </button>
+                  <OpenAIFastPolicyUserSelector
+                    :model-value="rule.user_ids || []"
+                    @update:model-value="rule.user_ids = $event"
+                  />
                 </div>
 
                 <!-- Error Message (only when action=block) -->
@@ -7431,6 +7381,7 @@ import ProxySelector from "@/components/common/ProxySelector.vue";
 import ImageUpload from "@/components/common/ImageUpload.vue";
 import BackupSettings from "@/views/admin/BackupView.vue";
 import EmailTemplateEditor from "@/views/admin/settings/EmailTemplateEditor.vue";
+import OpenAIFastPolicyUserSelector from "@/views/admin/settings/OpenAIFastPolicyUserSelector.vue";
 import { useClipboard } from "@/composables/useClipboard";
 import { affiliatesAPI, type AffiliateAdminEntry, type SimpleUser as AffiliateSimpleUser } from "@/api/admin/affiliates";
 import { extractApiErrorMessage, extractI18nErrorMessage } from "@/utils/apiError";
@@ -10226,18 +10177,6 @@ function removeOpenAIFastPolicyRule(index: number) {
   openaiFastPolicyForm.rules.splice(index, 1);
 }
 
-function addOpenAIFastPolicyUserID(rule: OpenAIFastPolicyRule) {
-  if (!rule.user_ids) rule.user_ids = [];
-  rule.user_ids.push(0);
-}
-
-function removeOpenAIFastPolicyUserID(
-  rule: OpenAIFastPolicyRule,
-  idx: number,
-) {
-  rule.user_ids?.splice(idx, 1);
-}
-
 function addOpenAIFastPolicyModelPattern(rule: OpenAIFastPolicyRule) {
   if (!rule.model_whitelist) rule.model_whitelist = [];
   rule.model_whitelist.push("");
diff --git a/frontend/src/views/admin/settings/OpenAIFastPolicyUserSelector.vue b/frontend/src/views/admin/settings/OpenAIFastPolicyUserSelector.vue
new file mode 100644
index 0000000000..0b25c876ad
--- /dev/null
+++ b/frontend/src/views/admin/settings/OpenAIFastPolicyUserSelector.vue
@@ -0,0 +1,229 @@
+<template>
+  <div ref="containerRef" class="relative">
+    <div v-if="selectedUserIds.length > 0" class="mb-2 flex flex-wrap gap-2">
+      <span
+        v-for="userId in selectedUserIds"
+        :key="userId"
+        class="inline-flex max-w-full items-center gap-1.5 rounded-md bg-gray-100 px-2.5 py-1.5 text-xs text-gray-700 dark:bg-dark-600 dark:text-gray-200"
+      >
+        <span class="max-w-64 truncate font-medium" :title="selectedUserLabel(userId)">
+          {{ selectedUserLabel(userId) }}
+        </span>
+        <span class="shrink-0 text-gray-400">#{{ userId }}</span>
+        <span
+          v-if="selectedUsers[userId]?.deleted"
+          class="shrink-0 text-gray-400"
+        >
+          {{ t("admin.settings.openaiFastPolicy.userDeleted") }}
+        </span>
+        <button
+          type="button"
+          class="shrink-0 rounded text-gray-400 hover:text-red-600 dark:hover:text-red-400"
+          :aria-label="t('admin.settings.openaiFastPolicy.removeUser')"
+          :title="t('admin.settings.openaiFastPolicy.removeUser')"
+          @click="removeUser(userId)"
+        >
+          <Icon name="x" size="xs" :stroke-width="2" />
+        </button>
+      </span>
+    </div>
+
+    <div class="relative">
+      <Icon
+        name="search"
+        size="sm"
+        class="pointer-events-none absolute left-3 top-1/2 -translate-y-1/2 text-gray-400"
+      />
+      <input
+        v-model="searchQuery"
+        type="text"
+        autocomplete="off"
+        class="input input-sm w-full pl-9"
+        :placeholder="t('admin.settings.openaiFastPolicy.userSearchPlaceholder')"
+        @input="debounceSearch"
+        @focus="showDropdown = true"
+      />
+    </div>
+
+    <div
+      v-if="showDropdown && searchQuery.trim()"
+      class="absolute z-50 mt-1 max-h-60 w-full overflow-auto rounded-lg border border-gray-200 bg-white shadow-lg dark:border-dark-600 dark:bg-dark-700"
+    >
+      <div v-if="searchLoading" class="px-4 py-3 text-sm text-gray-500 dark:text-gray-400">
+        {{ t("common.loading") }}
+      </div>
+      <div
+        v-else-if="availableResults.length === 0"
+        class="px-4 py-3 text-sm text-gray-500 dark:text-gray-400"
+      >
+        {{ t("admin.settings.openaiFastPolicy.userSearchEmpty") }}
+      </div>
+      <template v-else>
+        <button
+          v-for="user in availableResults"
+          :key="user.id"
+          type="button"
+          class="flex w-full items-center justify-between gap-3 px-4 py-2 text-left text-sm hover:bg-gray-100 dark:hover:bg-dark-600"
+          @click="selectUser(user)"
+        >
+          <span class="min-w-0 truncate font-medium text-gray-900 dark:text-white">
+            {{ user.email }}
+            <span v-if="user.deleted" class="ml-1 text-xs font-normal text-gray-400">
+              {{ t("admin.settings.openaiFastPolicy.userDeleted") }}
+            </span>
+          </span>
+          <span class="shrink-0 text-xs text-gray-400">#{{ user.id }}</span>
+        </button>
+      </template>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { computed, onMounted, onUnmounted, ref, watch } from "vue";
+import { useI18n } from "vue-i18n";
+import { adminAPI } from "@/api/admin";
+import type { SimpleUser } from "@/api/admin/usage";
+import Icon from "@/components/icons/Icon.vue";
+
+const props = defineProps<{
+  modelValue: number[];
+}>();
+
+const emit = defineEmits<{
+  "update:modelValue": [value: number[]];
+}>();
+
+const { t } = useI18n();
+const containerRef = ref<HTMLElement | null>(null);
+const searchQuery = ref("");
+const searchResults = ref<SimpleUser[]>([]);
+const searchLoading = ref(false);
+const showDropdown = ref(false);
+const selectedUsers = ref<Record<number, SimpleUser>>({});
+let searchTimer: ReturnType<typeof setTimeout> | null = null;
+let searchSequence = 0;
+
+const selectedUserIds = computed(() =>
+  Array.from(new Set(props.modelValue.filter((id) => Number.isInteger(id) && id > 0))),
+);
+
+const availableResults = computed(() => {
+  const selected = new Set(selectedUserIds.value);
+  return searchResults.value
+    .filter((user) => !selected.has(user.id))
+    .sort((a, b) => Number(a.deleted) - Number(b.deleted));
+});
+
+function selectedUserLabel(userId: number): string {
+  return selectedUsers.value[userId]?.email ||
+    t("admin.settings.openaiFastPolicy.userIdFallback", { id: userId });
+}
+
+function clearPendingSearch(): void {
+  if (searchTimer) {
+    clearTimeout(searchTimer);
+    searchTimer = null;
+  }
+  searchSequence += 1;
+}
+
+function debounceSearch(): void {
+  clearPendingSearch();
+  const query = searchQuery.value.trim();
+  showDropdown.value = true;
+  if (!query) {
+    searchResults.value = [];
+    searchLoading.value = false;
+    return;
+  }
+
+  const sequence = searchSequence;
+  searchTimer = setTimeout(async () => {
+    searchLoading.value = true;
+    try {
+      const results = await adminAPI.usage.searchUsers(query);
+      if (sequence === searchSequence) {
+        searchResults.value = results;
+      }
+    } catch {
+      if (sequence === searchSequence) {
+        searchResults.value = [];
+      }
+    } finally {
+      if (sequence === searchSequence) {
+        searchLoading.value = false;
+      }
+    }
+  }, 300);
+}
+
+function selectUser(user: SimpleUser): void {
+  selectedUsers.value = { ...selectedUsers.value, [user.id]: user };
+  emit("update:modelValue", [...selectedUserIds.value, user.id]);
+  clearPendingSearch();
+  searchQuery.value = "";
+  searchResults.value = [];
+  searchLoading.value = false;
+  showDropdown.value = false;
+}
+
+function removeUser(userId: number): void {
+  emit(
+    "update:modelValue",
+    selectedUserIds.value.filter((id) => id !== userId),
+  );
+}
+
+async function hydrateSelectedUsers(userIds: number[]): Promise<void> {
+  const missing = userIds.filter((id) => !selectedUsers.value[id]);
+  if (missing.length === 0) return;
+
+  const users = await Promise.all(
+    missing.map(async (id) => {
+      try {
+        const user = await adminAPI.users.getById(id, true);
+        return {
+          id: user.id,
+          email: user.email,
+          deleted: Boolean(user.deleted_at),
+        } satisfies SimpleUser;
+      } catch {
+        return null;
+      }
+    }),
+  );
+
+  const next = { ...selectedUsers.value };
+  for (const user of users) {
+    if (user && props.modelValue.includes(user.id)) {
+      next[user.id] = user;
+    }
+  }
+  selectedUsers.value = next;
+}
+
+function handleDocumentClick(event: MouseEvent): void {
+  const target = event.target as Node | null;
+  if (target && !containerRef.value?.contains(target)) {
+    showDropdown.value = false;
+  }
+}
+
+watch(
+  selectedUserIds,
+  (userIds) => {
+    void hydrateSelectedUsers(userIds);
+  },
+  { immediate: true },
+);
+
+onMounted(() => {
+  document.addEventListener("click", handleDocumentClick);
+});
+
+onUnmounted(() => {
+  clearPendingSearch();
+  document.removeEventListener("click", handleDocumentClick);
+});
+</script>
diff --git a/frontend/src/views/admin/settings/__tests__/OpenAIFastPolicyUserSelector.spec.ts b/frontend/src/views/admin/settings/__tests__/OpenAIFastPolicyUserSelector.spec.ts
new file mode 100644
index 0000000000..c8e1f0e1cf
--- /dev/null
+++ b/frontend/src/views/admin/settings/__tests__/OpenAIFastPolicyUserSelector.spec.ts
@@ -0,0 +1,112 @@
+import { flushPromises, mount } from '@vue/test-utils'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+
+import OpenAIFastPolicyUserSelector from '../OpenAIFastPolicyUserSelector.vue'
+
+const messages: Record<string, string> = {
+  'admin.settings.openaiFastPolicy.userDeleted': '(deleted)',
+  'admin.settings.openaiFastPolicy.userIdFallback': 'User #{id}',
+  'admin.settings.openaiFastPolicy.removeUser': 'Remove user',
+  'admin.settings.openaiFastPolicy.userSearchPlaceholder': 'Search users',
+  'admin.settings.openaiFastPolicy.userSearchEmpty': 'No users found',
+  'common.loading': 'Loading',
+}
+
+vi.mock('vue-i18n', () => ({
+  useI18n: () => ({
+    t: (key: string, params?: Record<string, unknown>) => {
+      const message = messages[key] ?? key
+      return params
+        ? Object.entries(params).reduce(
+            (value, [name, replacement]) => value.replace(`{${name}}`, String(replacement)),
+            message,
+          )
+        : message
+    },
+  }),
+}))
+
+const mockSearchUsers = vi.fn()
+const mockGetUserById = vi.fn()
+
+vi.mock('@/api/admin', () => ({
+  adminAPI: {
+    usage: {
+      searchUsers: (...args: unknown[]) => mockSearchUsers(...args),
+    },
+    users: {
+      getById: (...args: unknown[]) => mockGetUserById(...args),
+    },
+  },
+}))
+
+describe('OpenAIFastPolicyUserSelector', () => {
+  beforeEach(() => {
+    vi.useFakeTimers()
+    mockSearchUsers.mockReset()
+    mockGetUserById.mockReset()
+  })
+
+  afterEach(() => {
+    vi.useRealTimers()
+  })
+
+  it('hydrates existing IDs to email labels without changing the saved IDs', async () => {
+    mockGetUserById.mockResolvedValue({
+      id: 7,
+      email: 'existing@example.com',
+      deleted_at: null,
+    })
+
+    const wrapper = mount(OpenAIFastPolicyUserSelector, {
+      props: { modelValue: [7] },
+      global: { stubs: { Icon: true } },
+    })
+    await flushPromises()
+
+    expect(mockGetUserById).toHaveBeenCalledWith(7, true)
+    expect(wrapper.text()).toContain('existing@example.com')
+    expect(wrapper.text()).toContain('#7')
+    expect(wrapper.emitted('update:modelValue')).toBeUndefined()
+  })
+
+  it('searches after one character and adds the selected user ID', async () => {
+    mockSearchUsers.mockResolvedValue([
+      { id: 9, email: 'alice@example.com', deleted: false },
+    ])
+
+    const wrapper = mount(OpenAIFastPolicyUserSelector, {
+      props: { modelValue: [] },
+      global: { stubs: { Icon: true } },
+    })
+    const input = wrapper.get('input')
+    await input.trigger('focus')
+    await input.setValue('a')
+    await input.trigger('input')
+    vi.advanceTimersByTime(300)
+    await flushPromises()
+
+    expect(mockSearchUsers).toHaveBeenCalledWith('a')
+    const result = wrapper.findAll('button').find((button) =>
+      button.text().includes('alice@example.com'),
+    )
+    expect(result).toBeDefined()
+    await result!.trigger('click')
+
+    expect(wrapper.emitted('update:modelValue')).toEqual([[[9]]])
+  })
+
+  it('keeps an unresolved saved ID visible and removable', async () => {
+    mockGetUserById.mockRejectedValue(new Error('not found'))
+
+    const wrapper = mount(OpenAIFastPolicyUserSelector, {
+      props: { modelValue: [42] },
+      global: { stubs: { Icon: true } },
+    })
+    await flushPromises()
+
+    expect(wrapper.text()).toContain('User #42')
+    await wrapper.get('button[aria-label="Remove user"]').trigger('click')
+    expect(wrapper.emitted('update:modelValue')).toEqual([[[]]])
+  })
+})