diff --git a/src/services/ecosystem/handlers/wallet.test.ts b/src/services/ecosystem/handlers/wallet.test.ts
new file mode 100644
index 000000000..811db7026
--- /dev/null
+++ b/src/services/ecosystem/handlers/wallet.test.ts
@@ -0,0 +1,47 @@
+import { describe, it, expect, beforeEach } from 'vitest'
+import { handleChainId } from './wallet'
+import { walletStore } from '@/stores/wallet'
+import type { HandlerContext } from '../types'
+
+describe('handleChainId', () => {
+  const mockContext: HandlerContext = {
+    appId: 'test-app',
+    appName: 'Test App',
+    origin: 'https://test.com',
+    permissions: [],
+  }
+
+  beforeEach(() => {
+    // Reset store state
+    walletStore.setState(() => ({
+      wallets: [],
+      currentWalletId: null,
+      selectedChain: 'bfmeta',
+      chainPreferences: {},
+      isLoading: false,
+      isInitialized: false,
+      migrationRequired: false,
+    }))
+  })
+
+  it('should return the currently selected chain ID', async () => {
+    // Set a different chain
+    walletStore.setState((state) => ({
+      ...state,
+      selectedChain: 'ethereum',
+    }))
+
+    const chainId = await handleChainId({}, mockContext)
+    expect(chainId).toBe('ethereum')
+  })
+
+  it('should return bfmeta if that is the selected chain', async () => {
+    walletStore.setState((state) => ({
+      ...state,
+      selectedChain: 'bfmeta',
+    }))
+
+    const chainId = await handleChainId({}, mockContext)
+    expect(chainId).toBe('bfmeta')
+  })
+})
diff --git a/src/services/ecosystem/handlers/wallet.ts b/src/services/ecosystem/handlers/wallet.ts
index 6a58b14eb..b7236dfe3 100644
--- a/src/services/ecosystem/handlers/wallet.ts
+++ b/src/services/ecosystem/handlers/wallet.ts
@@ -6,6 +6,7 @@ import type { MethodHandler, BioAccount } from '../types'
 import { BioErrorCodes } from '../types'
 import { HandlerContext } from './context'
 import { getChainProvider } from '@/services/chain-adapter/providers'
+import { walletStore } from '@/stores/wallet'
 
 // 兼容旧 API，逐步迁移到 HandlerContext
 let _showWalletPicker: ((opts?: { chain?: string; exclude?: string }) => Promise<BioAccount | null>) | null = null
@@ -104,8 +105,7 @@ export const handlePickWallet: MethodHandler = async (params, context) => {
 
 /** bio_chainId - Get current chain ID */
 export const handleChainId: MethodHandler = async (_params, _context) => {
-  // TODO: Get from current selected chain
-  return 'bfmeta'
+  return walletStore.state.selectedChain
 }
 
 /** bio_getBalance - Get balance */