diff --git a/backend/services/identity-service/test/app.e2e-spec.ts b/backend/services/identity-service/test/app.e2e-spec.ts
index 27f7eae7..d41f9af8 100644
--- a/backend/services/identity-service/test/app.e2e-spec.ts
+++ b/backend/services/identity-service/test/app.e2e-spec.ts
@@ -57,6 +57,20 @@ describe('Identity Service E2E Tests', () => {
     prisma = app.get<PrismaService>(PrismaService);
 
     await app.init();
+
+    // 清理数据库，为测试准备干净的环境
+    await prisma.userDevice.deleteMany();
+    await prisma.walletAddress.deleteMany();
+    await prisma.userAccount.deleteMany();
+
+    // 初始化账户序列号生成器
+    await prisma.accountSequenceGenerator.deleteMany();
+    await prisma.accountSequenceGenerator.create({
+      data: {
+        id: 1,
+        currentSequence: BigInt(100000),
+      },
+    });
   });
 
   afterAll(async () => {
@@ -233,16 +247,30 @@ describe('Identity Service E2E Tests', () => {
     });
 
     it('应该限制设备数量为5个', async () => {
-      // 添加5个设备
-      for (let i = 0; i < 5; i++) {
+      // 创建新的独立账户用于测试设备限制（包含1个初始设备）
+      const newAccount = await request(app.getHttpServer())
+        .post('/api/v1/user/auto-create')
+        .send({
+          deviceId: `limit-test-initial-${Date.now()}`,
+          deviceName: 'Initial Device',
+          provinceCode: '110000',
+          cityCode: '110100',
+        })
+        .expect(201);
+
+      const testAccountSequence = newAccount.body.data.accountSequence;
+      const testMnemonic = newAccount.body.data.mnemonic;
+
+      // 再添加4个设备，达到5个限制
+      for (let i = 0; i < 4; i++) {
         const testDeviceId = `test-device-limit-${Date.now()}-${i}`;
         const response = await request(app.getHttpServer())
           .post('/api/v1/user/recover-by-mnemonic')
           .send({
-            accountSequence,
-            mnemonic,
+            accountSequence: testAccountSequence,
+            mnemonic: testMnemonic,
             newDeviceId: testDeviceId,
-            deviceName: `设备${i + 1}`,
+            deviceName: `设备${i + 2}`, // 从设备2开始命名（设备1是初始设备）
           });
 
         if (response.status !== 201) {
@@ -255,13 +283,13 @@ describe('Identity Service E2E Tests', () => {
         expect(response.status).toBe(201);
       }
 
-      // 尝试添加第6个设备，应该失败
+      // 现在已经有5个设备了，尝试添加第6个设备，应该失败
       const sixthDeviceId = `test-device-sixth-${Date.now()}`;
       await request(app.getHttpServer())
         .post('/api/v1/user/recover-by-mnemonic')
         .send({
-          accountSequence,
-          mnemonic,
+          accountSequence: testAccountSequence,
+          mnemonic: testMnemonic,
           newDeviceId: sixthDeviceId,
           deviceName: '第6个设备',
         })