diff --git a/frontend/src/stores/__tests__/dashboard.spec.ts b/frontend/src/stores/__tests__/dashboard.spec.ts
new file mode 100644
index 0000000..6effef2
--- /dev/null
+++ b/frontend/src/stores/__tests__/dashboard.spec.ts
@@ -0,0 +1,208 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { setActivePinia, createPinia } from 'pinia'
+import { useDashboardStore } from '../dashboard'
+
+vi.mock('@/utils/request', () => ({
+  api: {
+    get: vi.fn(),
+    post: vi.fn(),
+    put: vi.fn(),
+    delete: vi.fn(),
+  },
+}))
+
+const mockOverview = {
+  today: { success: 10, failed: 2 },
+  this_week: { success: 50, failed: 5 },
+  this_month: { success: 200, failed: 20 },
+  by_type: [
+    { data_type: 'order', success: 80, failed: 10 },
+    { data_type: 'product', success: 60, failed: 5 },
+    { data_type: 'refund', success: 40, failed: 3 },
+    { data_type: 'inventory', success: 20, failed: 2 },
+  ],
+}
+
+const mockTrendData = [
+  { date: '2026-03-18', success: 30, failed: 2 },
+  { date: '2026-03-19', success: 25, failed: 3 },
+  { date: '2026-03-20', success: 40, failed: 1 },
+]
+
+const mockBreakdownData = [
+  { id: 1, name: 'Acme Corp', success: 100, failed: 10 },
+  { id: 2, name: 'Beta Inc', success: 80, failed: 5 },
+]
+
+describe('useDashboardStore', () => {
+  beforeEach(() => {
+    setActivePinia(createPinia())
+    vi.restoreAllMocks()
+  })
+
+  describe('initial state', () => {
+    it('S1: starts with correct initial state', () => {
+      const store = useDashboardStore()
+      expect(store.overview).toBeNull()
+      expect(store.overviewLoading).toBe(false)
+      expect(store.trendData).toEqual([])
+      expect(store.trendGroupBy).toBe('day')
+      expect(store.breakdownData).toEqual([])
+      expect(store.breakdownDimension).toBe('company')
+    })
+  })
+
+  describe('fetchOverview', () => {
+    it('S2: fetches overview data successfully', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockResolvedValueOnce(mockOverview)
+
+      const store = useDashboardStore()
+      await store.fetchOverview()
+
+      expect(api.get).toHaveBeenCalledWith('/api/v1/dashboard/overview')
+      expect(store.overview).toEqual(mockOverview)
+      expect(store.overviewLoading).toBe(false)
+      expect(store.overviewError).toBe('')
+    })
+
+    it('S3: handles overview fetch error', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockRejectedValueOnce(new Error('网络错误'))
+
+      const store = useDashboardStore()
+      await store.fetchOverview()
+
+      expect(store.overview).toBeNull()
+      expect(store.overviewError).toBe('网络错误')
+      expect(store.overviewLoading).toBe(false)
+    })
+  })
+
+  describe('fetchTrend', () => {
+    it('S4: fetches trend data with default params', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockResolvedValueOnce(mockTrendData)
+
+      const store = useDashboardStore()
+      await store.fetchTrend()
+
+      expect(api.get).toHaveBeenCalledWith('/api/v1/dashboard/trend', expect.objectContaining({
+        group_by: 'day',
+      }))
+      expect(store.trendData).toEqual(mockTrendData)
+    })
+
+    it('S5: passes filter params to trend API', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockResolvedValueOnce(mockTrendData)
+
+      const store = useDashboardStore()
+      store.trendGroupBy = 'week'
+      store.trendDataType = 'order'
+      store.trendFrom = '2026-03-01'
+      store.trendTo = '2026-03-20'
+      await store.fetchTrend()
+
+      expect(api.get).toHaveBeenCalledWith('/api/v1/dashboard/trend', expect.objectContaining({
+        group_by: 'week',
+        data_type: 'order',
+        from: '2026-03-01',
+        to: '2026-03-20',
+      }))
+    })
+
+    it('S6: handles trend fetch error', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockRejectedValueOnce(new Error('趋势接口超时'))
+
+      const store = useDashboardStore()
+      await store.fetchTrend()
+
+      expect(store.trendData).toEqual([])
+      expect(store.trendError).toBe('趋势接口超时')
+    })
+  })
+
+  describe('fetchBreakdown', () => {
+    it('S7: fetches breakdown data with default params', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockResolvedValueOnce(mockBreakdownData)
+
+      const store = useDashboardStore()
+      await store.fetchBreakdown()
+
+      expect(api.get).toHaveBeenCalledWith('/api/v1/dashboard/breakdown', expect.objectContaining({
+        dimension: 'company',
+      }))
+      expect(store.breakdownData).toEqual(mockBreakdownData)
+    })
+
+    it('S8: passes filter params to breakdown API', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockResolvedValueOnce(mockBreakdownData)
+
+      const store = useDashboardStore()
+      store.breakdownDimension = 'store'
+      store.breakdownDataType = 'refund'
+      store.breakdownFrom = '2026-03-01'
+      store.breakdownTo = '2026-03-20'
+      await store.fetchBreakdown()
+
+      expect(api.get).toHaveBeenCalledWith('/api/v1/dashboard/breakdown', expect.objectContaining({
+        dimension: 'store',
+        data_type: 'refund',
+        from: '2026-03-01',
+        to: '2026-03-20',
+      }))
+    })
+
+    it('S9: handles breakdown fetch error', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockRejectedValueOnce(new Error('分维度接口失败'))
+
+      const store = useDashboardStore()
+      await store.fetchBreakdown()
+
+      expect(store.breakdownData).toEqual([])
+      expect(store.breakdownError).toBe('分维度接口失败')
+    })
+  })
+
+  describe('fetchAll', () => {
+    it('S10: calls all three fetch functions in parallel', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockImplementation((url: string) => {
+        if (url.includes('overview')) return Promise.resolve(mockOverview) as never
+        if (url.includes('trend')) return Promise.resolve(mockTrendData) as never
+        if (url.includes('breakdown')) return Promise.resolve(mockBreakdownData) as never
+        return Promise.resolve(null) as never
+      })
+
+      const store = useDashboardStore()
+      await store.fetchAll()
+
+      expect(store.overview).toEqual(mockOverview)
+      expect(store.trendData).toEqual(mockTrendData)
+      expect(store.breakdownData).toEqual(mockBreakdownData)
+    })
+
+    it('S11: one API failure does not block others', async () => {
+      const { api } = await import('@/utils/request')
+      vi.mocked(api.get).mockImplementation((url: string) => {
+        if (url.includes('overview')) return Promise.reject(new Error('概览失败')) as never
+        if (url.includes('trend')) return Promise.resolve(mockTrendData) as never
+        if (url.includes('breakdown')) return Promise.resolve(mockBreakdownData) as never
+        return Promise.resolve(null) as never
+      })
+
+      const store = useDashboardStore()
+      await store.fetchAll()
+
+      expect(store.overview).toBeNull()
+      expect(store.overviewError).toBe('概览失败')
+      expect(store.trendData).toEqual(mockTrendData)
+      expect(store.breakdownData).toEqual(mockBreakdownData)
+    })
+  })
+})
diff --git a/frontend/src/stores/dashboard.ts b/frontend/src/stores/dashboard.ts
new file mode 100644
index 0000000..5b89480
--- /dev/null
+++ b/frontend/src/stores/dashboard.ts
@@ -0,0 +1,125 @@
+import { api } from '@/utils/request'
+import type {
+  DashboardOverview,
+  DashboardTrendPoint,
+  DashboardTrendParams,
+  DashboardBreakdownItem,
+  DashboardBreakdownParams,
+} from '@/types/api'
+
+export const useDashboardStore = defineStore('dashboard', () => {
+  // ─── Overview ───
+  const overview = ref<DashboardOverview | null>(null)
+  const overviewLoading = ref(false)
+  const overviewError = ref('')
+
+  // ─── Trend ───
+  const trendData = ref<DashboardTrendPoint[]>([])
+  const trendLoading = ref(false)
+  const trendError = ref('')
+  const trendGroupBy = ref<'day' | 'week' | 'month'>('day')
+  const trendDataType = ref<string | undefined>(undefined)
+  const trendFrom = ref<string | undefined>(undefined)
+  const trendTo = ref<string | undefined>(undefined)
+
+  // ─── Breakdown ───
+  const breakdownData = ref<DashboardBreakdownItem[]>([])
+  const breakdownLoading = ref(false)
+  const breakdownError = ref('')
+  const breakdownDimension = ref<'company' | 'platform' | 'store'>('company')
+  const breakdownDataType = ref<string | undefined>(undefined)
+  const breakdownFrom = ref<string | undefined>(undefined)
+  const breakdownTo = ref<string | undefined>(undefined)
+
+  async function fetchOverview() {
+    overviewLoading.value = true
+    overviewError.value = ''
+    try {
+      overview.value = await api.get<DashboardOverview>('/api/v1/dashboard/overview')
+    } catch (err: unknown) {
+      const msg = err instanceof Error ? err.message : '获取概览数据失败'
+      overviewError.value = msg
+      message.error(msg)
+    } finally {
+      overviewLoading.value = false
+    }
+  }
+
+  async function fetchTrend() {
+    trendLoading.value = true
+    trendError.value = ''
+    try {
+      const params: DashboardTrendParams = {
+        group_by: trendGroupBy.value,
+        data_type: trendDataType.value,
+        from: trendFrom.value,
+        to: trendTo.value,
+      }
+      trendData.value = await api.get<DashboardTrendPoint[]>(
+        '/api/v1/dashboard/trend',
+        params as unknown as Record<string, unknown>,
+      )
+    } catch (err: unknown) {
+      const msg = err instanceof Error ? err.message : '获取趋势数据失败'
+      trendError.value = msg
+      message.error(msg)
+    } finally {
+      trendLoading.value = false
+    }
+  }
+
+  async function fetchBreakdown() {
+    breakdownLoading.value = true
+    breakdownError.value = ''
+    try {
+      const params: DashboardBreakdownParams = {
+        dimension: breakdownDimension.value,
+        data_type: breakdownDataType.value,
+        from: breakdownFrom.value,
+        to: breakdownTo.value,
+      }
+      breakdownData.value = await api.get<DashboardBreakdownItem[]>(
+        '/api/v1/dashboard/breakdown',
+        params as unknown as Record<string, unknown>,
+      )
+    } catch (err: unknown) {
+      const msg = err instanceof Error ? err.message : '获取分维度数据失败'
+      breakdownError.value = msg
+      message.error(msg)
+    } finally {
+      breakdownLoading.value = false
+    }
+  }
+
+  async function fetchAll() {
+    await Promise.allSettled([fetchOverview(), fetchTrend(), fetchBreakdown()])
+  }
+
+  return {
+    // Overview
+    overview,
+    overviewLoading,
+    overviewError,
+    // Trend
+    trendData,
+    trendLoading,
+    trendError,
+    trendGroupBy,
+    trendDataType,
+    trendFrom,
+    trendTo,
+    // Breakdown
+    breakdownData,
+    breakdownLoading,
+    breakdownError,
+    breakdownDimension,
+    breakdownDataType,
+    breakdownFrom,
+    breakdownTo,
+    // Actions
+    fetchOverview,
+    fetchTrend,
+    fetchBreakdown,
+    fetchAll,
+  }
+})
diff --git a/frontend/src/types/api.ts b/frontend/src/types/api.ts
index c781375..13cfd97 100644
--- a/frontend/src/types/api.ts
+++ b/frontend/src/types/api.ts
@@ -208,6 +208,51 @@ export interface FailedMessageFilters {
   failed_at_range: [string, string] | null
 }
 
+/** ─── Dashboard 统计 ─── */
+
+export interface SuccessFailedCount {
+  success: number
+  failed: number
+}
+
+export interface DataTypeCount extends SuccessFailedCount {
+  data_type: string
+}
+
+export interface DashboardOverview {
+  today: SuccessFailedCount
+  this_week: SuccessFailedCount
+  this_month: SuccessFailedCount
+  by_type: DataTypeCount[]
+}
+
+export interface DashboardTrendPoint {
+  date: string
+  success: number
+  failed: number
+}
+
+export interface DashboardTrendParams {
+  from?: string
+  to?: string
+  group_by?: 'day' | 'week' | 'month'
+  data_type?: string
+}
+
+export interface DashboardBreakdownItem {
+  id: number
+  name: string
+  success: number
+  failed: number
+}
+
+export interface DashboardBreakdownParams {
+  dimension?: 'company' | 'platform' | 'store'
+  from?: string
+  to?: string
+  data_type?: string
+}
+
 /** 业务异常 */
 export class ApiError extends Error {
   code: number