diff --git a/admin-frontend-vue/src/pages/shop/shop-group-model.ts b/admin-frontend-vue/src/pages/shop/shop-group-model.ts
new file mode 100644
index 00000000..893904b1
--- /dev/null
+++ b/admin-frontend-vue/src/pages/shop/shop-group-model.ts
@@ -0,0 +1,34 @@
+/** 店铺分组选项解析模型（任务 90）：解析 ShopManageGroupItemVo 数组为下拉选项，纯逻辑。 */
+import { unwrap } from '../../api/envelope.ts'
+import type { ShopGroupOption } from './shop-dto.ts'
+
+function text(value: unknown): string {
+  return typeof value === 'string' ? value.trim() : ''
+}
+
+function numberOrNull(value: unknown): number | null {
+  return typeof value === 'number' && Number.isFinite(value) ? Math.floor(value) : null
+}
+
+/** 解析单条分组下拉项；缺 id 视为无效。 */
+export function toShopGroupOption(raw: unknown): ShopGroupOption | null {
+  if (!raw || typeof raw !== 'object') return null
+  const record = raw as Record<string, unknown>
+  const id = numberOrNull(record.id)
+  if (id === null) return null
+  const option: ShopGroupOption = { id, groupName: text(record.groupName ?? record.group_name) }
+  const memberCount = numberOrNull(record.memberCount ?? record.member_count)
+  if (memberCount !== null) option.memberCount = memberCount
+  const leaderUsername = text(record.leaderUsername ?? record.leader_username)
+  if (leaderUsername) option.leaderUsername = leaderUsername
+  return option
+}
+
+/** 归一化分组下拉负载（信封或已解包数组）为选项列表；空/无效项过滤。 */
+export function parseShopManageGroups(payload: unknown): ShopGroupOption[] {
+  const data = unwrap<unknown>(payload)
+  if (!Array.isArray(data)) return []
+  return data
+    .map((raw) => toShopGroupOption(raw))
+    .filter((option): option is ShopGroupOption => option !== null)
+}
diff --git a/admin-frontend-vue/src/pages/shop/shop-manage-api.ts b/admin-frontend-vue/src/pages/shop/shop-manage-api.ts
index ed9101bc..aebbcfa0 100644
--- a/admin-frontend-vue/src/pages/shop/shop-manage-api.ts
+++ b/admin-frontend-vue/src/pages/shop/shop-manage-api.ts
@@ -1,9 +1,11 @@
-/** 店铺列表加载适配（任务 88）：GET /api/admin/shop-manages + 分页/筛选归一与解析。 */
+/** 店铺列表加载与分组选项适配（任务 88/90）：GET /api/admin/shop-manages(/groups) + 归一与解析。 */
 import { http } from '@/api/http'
 import { parseShopManagePage } from './shop-manage-model.ts'
+import { parseShopManageGroups } from './shop-group-model.ts'
 import {
   normalizeShopListParams,
   toShopManagePageQuery,
+  type ShopGroupOption,
   type ShopManageListParams,
   type ShopPageResult,
 } from './shop-dto.ts'
@@ -15,3 +17,11 @@ export async function fetchShopManageList(params: Partial<ShopManageListParams>
   const { data } = await http.get<unknown>(SHOP_MANAGE_ENDPOINT, { params: toShopManagePageQuery(normalized) })
   return parseShopManagePage(data)
 }
+
+export const SHOP_MANAGE_GROUPS_ENDPOINT = '/api/admin/shop-manages/groups'
+
+/** 加载店铺分组下拉选项（超级管理员取全部，普通管理员由后端限定可访问分组）。 */
+export async function fetchShopManageGroups(): Promise<ShopGroupOption[]> {
+  const { data } = await http.get<unknown>(SHOP_MANAGE_GROUPS_ENDPOINT)
+  return parseShopManageGroups(data)
+}
diff --git a/admin-frontend-vue/tests/task-90.test.ts b/admin-frontend-vue/tests/task-90.test.ts
new file mode 100644
index 00000000..1eb46cf6
--- /dev/null
+++ b/admin-frontend-vue/tests/task-90.test.ts
@@ -0,0 +1,72 @@
+import test from 'node:test'
+import assert from 'node:assert/strict'
+import { readSource } from './helpers.ts'
+import { parseShopManageGroups, toShopGroupOption } from '../src/pages/shop/shop-group-model.ts'
+
+test('test_task_090_shop_group_options_load_normal_primary_path', () => {
+  // 正常主路径：Java ShopManageGroupItemVo 数组封包解析为分组下拉项。
+  const options = parseShopManageGroups({
+    success: true,
+    data: [
+      { id: 1, groupName: '华东组', memberCount: 3, leaderUsername: '张' },
+      { id: 2, groupName: '华南组', memberCount: 5 },
+    ],
+  })
+  assert.equal(options.length, 2)
+  assert.equal(options[0].id, 1)
+  assert.equal(options[0].groupName, '华东组')
+  assert.equal(options[0].memberCount, 3)
+  assert.equal(options[0].leaderUsername, '张')
+  assert.equal(options[1].id, 2)
+})
+
+test('test_task_090_shop_group_options_load_normal_variant_input', () => {
+  // 正常变体：可选字段缺失时下拉仍可用。
+  const option = toShopGroupOption({ id: 7, groupName: '备用组' })
+  assert.ok(option)
+  assert.equal(option.id, 7)
+  assert.equal(option.groupName, '备用组')
+  assert.equal(option.memberCount, undefined)
+  assert.equal(option.leaderUsername, undefined)
+})
+
+test('test_task_090_shop_group_options_load_repeated_is_idempotent', () => {
+  // 正常重复：解析同一负载结果稳定、不改输入。
+  const payload = { data: [{ id: 1, groupName: 'A', memberCount: 1 }] }
+  assert.deepEqual(parseShopManageGroups(payload), parseShopManageGroups(payload))
+})
+
+test('test_task_090_shop_group_options_load_boundary_empty_input', () => {
+  // 边界空值：空数组/空负载返回空下拉选项。
+  assert.deepEqual(parseShopManageGroups({ data: [] }), [])
+  assert.deepEqual(parseShopManageGroups({}), [])
+})
+
+test('test_task_090_shop_group_options_load_boundary_single_item', () => {
+  // 边界单元素：单分组可下拉。
+  const options = parseShopManageGroups([{ id: 4, groupName: '单组' }])
+  assert.equal(options.length, 1)
+  assert.equal(options[0].groupName, '单组')
+})
+
+test('test_task_090_shop_group_options_load_boundary_limit_or_missing_field', () => {
+  // 边界上限/缺字段：成员数为非数字按缺省处理。
+  const option = toShopGroupOption({ id: 2, groupName: '组', memberCount: 'x' })
+  assert.equal(option!.memberCount, undefined)
+})
+
+test('test_task_090_shop_group_options_load_invalid_input_rejected', () => {
+  // 异常输入：缺 id 的分组不进入下拉；success=false 抛后端 message。
+  assert.equal(toShopGroupOption('garbage'), null)
+  assert.equal(toShopGroupOption({ groupName: 'no id' }), null)
+  assert.throws(() => parseShopManageGroups({ success: false, message: '无权访问分组' }), /无权访问/)
+})
+
+test('test_task_090_shop_group_options_load_dependency_failure_returns_actionable_message', () => {
+  // 依赖失败/加载走 adapter：GET /api/admin/shop-manages/groups + http.get + 解析。
+  const api = readSource('src/pages/shop/shop-manage-api.ts')
+  assert.match(api, /\/api\/admin\/shop-manages\/groups/)
+  assert.match(api, /fetchShopManageGroups/)
+  const model = readSource('src/pages/shop/shop-group-model.ts')
+  assert.equal(/axios|http\./.test(model), false, '分组解析保持纯逻辑')
+})