diff --git a/src/routes/admin/analytics.js b/src/routes/admin/analytics.js
index 68c3f5b..64143a5 100644
--- a/src/routes/admin/analytics.js
+++ b/src/routes/admin/analytics.js
@@ -11,7 +11,8 @@ const router = new Hono()
 router.get('/', asyncHandler(async (c) => {
   const period = c.req.query('period') || '30d'
   const stripeService = new StripeService(c.env.STRIPE_SECRET_KEY, c.env.SITE_URL)
-  const analyticsService = new AnalyticsService(stripeService)
+  const kvNamespace = getKVNamespace(c.env)
+  const analyticsService = new AnalyticsService(stripeService, kvNamespace)
   const analytics = await analyticsService.getAnalytics(period)
   return c.json(analytics)
 }))
diff --git a/src/services/AnalyticsService.js b/src/services/AnalyticsService.js
index 86a6da6..89e006e 100644
--- a/src/services/AnalyticsService.js
+++ b/src/services/AnalyticsService.js
@@ -2,8 +2,9 @@
 import { StripeService } from './StripeService.js'
 
 export class AnalyticsService {
-  constructor(stripeService) {
+  constructor(stripeService, kv = null) {
     this.stripe = stripeService
+    this.kv = kv
   }
 
   /**
@@ -11,7 +12,26 @@ export class AnalyticsService {
    */
   async getAnalytics(period = '30d') {
     const periodDays = { '1d': 1, '7d': 7, '30d': 30, '90d': 90, '1y': 365 }
-    const days = periodDays[period] || 30
+
+    // Sanitize period to prevent cache poisoning
+    if (!periodDays[period]) {
+      period = '30d'
+    }
+
+    // Check cache
+    if (this.kv) {
+      const cacheKey = `analytics:${period}`
+      const cached = await this.kv.get(cacheKey)
+      if (cached) {
+        try {
+          return JSON.parse(cached)
+        } catch (e) {
+          console.error('Error parsing cached analytics', e)
+        }
+      }
+    }
+
+    const days = periodDays[period]
     const now = new Date()
     const startDate = new Date(now.getTime() - (days * 24 * 60 * 60 * 1000))
 
@@ -76,7 +96,7 @@ export class AnalyticsService {
       }
     }
 
-    return {
+    const result = {
       period,
       totalRevenue: Math.round(totalRevenue * 100) / 100,
       totalOrders,
@@ -88,6 +108,15 @@ export class AnalyticsService {
         end: now.toISOString()
       }
     }
+
+    // Cache result
+    if (this.kv) {
+      const cacheKey = `analytics:${period}`
+      // Cache for 5 minutes
+      await this.kv.put(cacheKey, JSON.stringify(result), { expirationTtl: 300 })
+    }
+
+    return result
   }
 
   /**
diff --git a/tests/services/AnalyticsService.perf.test.js b/tests/services/AnalyticsService.perf.test.js
new file mode 100644
index 0000000..dc66efd
--- /dev/null
+++ b/tests/services/AnalyticsService.perf.test.js
@@ -0,0 +1,79 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { AnalyticsService } from '../../src/services/AnalyticsService.js'
+
+// Mock KV
+class MockKV {
+  constructor() {
+    this.store = new Map()
+  }
+  async get(key) {
+    return this.store.get(key)
+  }
+  async put(key, value) {
+    this.store.set(key, value)
+  }
+}
+
+// Mock Stripe Service
+class MockStripeService {
+  constructor() {
+    this.stripe = {
+        paymentIntents: {
+            list: async () => ({ data: [] })
+        }
+    }
+  }
+
+  async listPaymentIntents(startDate) {
+    // Simulate network delay
+    await new Promise(resolve => setTimeout(resolve, 50))
+    return {
+      data: Array(10).fill(0).map((_, i) => ({
+        id: `pi_${i}`,
+        status: 'succeeded',
+        amount: 1000,
+        created: Math.floor(Date.now() / 1000)
+      }))
+    }
+  }
+}
+
+describe('AnalyticsService Performance', () => {
+  let stripeService
+  let analyticsService
+  let kv
+
+  beforeEach(() => {
+    vi.clearAllMocks()
+    stripeService = new MockStripeService()
+    kv = new MockKV()
+
+    // We spy on the method to count calls
+    vi.spyOn(stripeService, 'listPaymentIntents')
+
+    // Initialize service
+    // Note: kv is passed but currently ignored by AnalyticsService
+    analyticsService = new AnalyticsService(stripeService, kv)
+  })
+
+  it('should verify cache behavior', async () => {
+    console.log('--- Starting Performance Test ---')
+
+    const start1 = performance.now()
+    await analyticsService.getAnalytics('30d')
+    const end1 = performance.now()
+    const time1 = end1 - start1
+
+    const start2 = performance.now()
+    await analyticsService.getAnalytics('30d')
+    const end2 = performance.now()
+    const time2 = end2 - start2
+
+    console.log(`Call 1 time: ${time1.toFixed(2)}ms`)
+    console.log(`Call 2 time: ${time2.toFixed(2)}ms`)
+
+    // With caching, the first call hits Stripe, the second hits cache.
+    // So we expect 1 call to Stripe.
+    expect(stripeService.listPaymentIntents).toHaveBeenCalledTimes(1)
+  })
+})