diff --git a/apps/web-wasm/src/components/ai/WebAIChat.vue b/apps/web-wasm/src/components/ai/WebAIChat.vue
index 883bd25f..a8a8ce05 100644
--- a/apps/web-wasm/src/components/ai/WebAIChat.vue
+++ b/apps/web-wasm/src/components/ai/WebAIChat.vue
@@ -9,7 +9,7 @@ import ConversationList from '@/components/AIChat/chat/ConversationList.vue'
 import SimpleAIChatInput from '@/components/AIChat/input/SimpleAIChatInput.vue'
 import { reportRuntimeLog } from '@/services/log-report'
 import { useLayoutStore } from '@/stores/layout'
-import { toWebAIChatMessage } from './message-mapper'
+import { toAIConversationListItem, toWebAIChatMessage } from './message-mapper'
 import { isAbortError, resolveSendTarget } from './send-lifecycle'
 import { useWebAISettingsStore } from '../../stores/web-ai-settings'
 
@@ -40,6 +40,7 @@ const displayMessages = computed(() => {
   if (streamingMessage.value) result.push(toWebAIChatMessage(streamingMessage.value, true))
   return result
 })
+const conversationListItems = computed(() => conversations.value.map(toAIConversationListItem))
 const canRetry = computed(() => messages.value.at(-1)?.role === 'user')
 const canRegenerate = computed(() => messages.value.at(-1)?.role === 'assistant')
 
@@ -376,7 +377,7 @@ function handleSend(payload: { content: string }) {
         :session-id="sessionId"
         :active-id="conversationId"
         :disabled="generating"
-        :conversations="conversations"
+        :conversations="conversationListItems"
         :loading="loading"
         :collapsible="false"
         embedded
@@ -392,7 +393,7 @@ function handleSend(payload: { content: string }) {
         :session-id="sessionId"
         :active-id="conversationId"
         :disabled="generating"
-        :conversations="conversations"
+        :conversations="conversationListItems"
         :loading="loading"
         @select="selectConversation"
         @create="newConversation"
diff --git a/apps/web-wasm/src/components/ai/message-mapper.test.ts b/apps/web-wasm/src/components/ai/message-mapper.test.ts
index 7c5fd013..01733831 100644
--- a/apps/web-wasm/src/components/ai/message-mapper.test.ts
+++ b/apps/web-wasm/src/components/ai/message-mapper.test.ts
@@ -1,7 +1,7 @@
 import assert from 'node:assert/strict'
 import { describe, it } from 'node:test'
 
-import { toWebAIContentBlocks } from './message-mapper'
+import { toAIConversationListItem, toWebAIContentBlocks } from './message-mapper'
 
 describe('toWebAIContentBlocks', () => {
   it('maps shared runtime blocks to the existing ChatLab message renderer', () => {
@@ -24,3 +24,21 @@ describe('toWebAIContentBlocks', () => {
     assert.equal(blocks[1]?.type === 'tool' ? blocks[1].tool.status : null, 'done')
   })
 })
+
+describe('toAIConversationListItem', () => {
+  it('normalizes Browser Runtime millisecond timestamps for the shared conversation list', () => {
+    const createdAt = Date.UTC(2025, 0, 1, 12)
+    const updatedAt = Date.UTC(2025, 5, 1, 12)
+
+    const item = toAIConversationListItem({
+      id: 'conversation-1',
+      sessionId: 'session-1',
+      title: 'Conversation',
+      createdAt,
+      updatedAt,
+    })
+
+    assert.equal(item.createdAt, Math.floor(createdAt / 1000))
+    assert.equal(item.updatedAt, Math.floor(updatedAt / 1000))
+  })
+})
diff --git a/apps/web-wasm/src/components/ai/message-mapper.ts b/apps/web-wasm/src/components/ai/message-mapper.ts
index d242fec8..7bf1a083 100644
--- a/apps/web-wasm/src/components/ai/message-mapper.ts
+++ b/apps/web-wasm/src/components/ai/message-mapper.ts
@@ -1,7 +1,16 @@
-import type { RuntimeContentBlock, RuntimeMessage } from '@openchatlab/ai-runtime'
+import type { RuntimeContentBlock, RuntimeConversation, RuntimeMessage } from '@openchatlab/ai-runtime'
 import type { ChatEvidencePayload } from '@openchatlab/core'
+import type { AIConversationListItem } from '@/components/AIChat/chat/ConversationList.vue'
 import type { ChatMessage, ContentBlock } from '@/stores/aiChat'
 
+export function toAIConversationListItem(conversation: RuntimeConversation): AIConversationListItem {
+  return {
+    ...conversation,
+    createdAt: Math.floor(conversation.createdAt / 1000),
+    updatedAt: Math.floor(conversation.updatedAt / 1000),
+  }
+}
+
 export function toWebAIContentBlocks(blocks: RuntimeContentBlock[] | undefined): ContentBlock[] {
   return (blocks ?? []).flatMap((block): ContentBlock[] => {
     if (block.type === 'text') return [{ type: 'text', text: block.text }]