diff --git a/src/components/AIChat/ChatExplorer.vue b/src/components/AIChat/ChatExplorer.vue
index f12e1826..66376f80 100644
--- a/src/components/AIChat/ChatExplorer.vue
+++ b/src/components/AIChat/ChatExplorer.vue
@@ -10,6 +10,7 @@ import AIChatInput from './input/AIChatInput.vue'
 import AIThinkingIndicator from './chat/AIThinkingIndicator.vue'
 import ChatStatusBar from './chat/ChatStatusBar.vue'
 import ChatHeaderActions from './chat/ChatHeaderActions.vue'
+import LoadingState from '@/components/UI/LoadingState.vue'
 import { useAIChat } from '@/composables/useAIChat'
 import { useAIService, useLLMService } from '@/services'
 import AssistantInlineBar from './assistant/AssistantInlineBar.vue'
@@ -46,12 +47,7 @@ const props = defineProps<{
   chatType?: 'group' | 'private'
 }>()
 
-const emit = defineEmits<{
-  'restore-loading-change': [loading: boolean]
-}>()
-
 const initialAIChatId = typeof route.query.aiChatId === 'string' ? route.query.aiChatId : null
-emit('restore-loading-change', true)
 
 // 使用 AI 对话 Composable
 const {
@@ -85,6 +81,19 @@ const {
 
 let isAIChatInitialized = false
 let isUnmounted = false
+const showRestoreLoading = ref(false)
+// 快速缓存恢复不显示遮罩，避免切换 Tab 时出现单帧闪屏；较慢恢复只覆盖 AI 内容区。
+let restoreLoadingTimer: ReturnType<typeof setTimeout> | null = setTimeout(() => {
+  showRestoreLoading.value = true
+}, 120)
+
+function finishRestoreLoading(): void {
+  if (restoreLoadingTimer) {
+    clearTimeout(restoreLoadingTimer)
+    restoreLoadingTimer = null
+  }
+  showRestoreLoading.value = false
+}
 
 function isCurrentSessionRoute(): boolean {
   const routeName = (props.chatType ?? 'group') === 'private' ? 'private-chat' : 'group-chat'
@@ -106,16 +115,16 @@ async function syncAIChatIdToRoute(aiChatId: string | null): Promise<void> {
 }
 
 void initialization.finally(() => {
+  finishRestoreLoading()
   if (!isCurrentSessionRoute()) return
 
-  emit('restore-loading-change', false)
   isAIChatInitialized = true
   void syncAIChatIdToRoute(currentAIChatId.value)
 })
 
 onUnmounted(() => {
   isUnmounted = true
-  emit('restore-loading-change', false)
+  finishRestoreLoading()
 })
 
 watch(currentAIChatId, (aiChatId) => {
@@ -472,7 +481,9 @@ watch(
 </script>
 
 <template>
-  <div class="main-content flex h-full overflow-hidden">
+  <div class="main-content relative flex h-full overflow-hidden">
+    <LoadingState v-if="showRestoreLoading" variant="overlay" />
+
     <!-- 左侧：对话记录列表（始终显示） -->
     <ConversationList
       ref="conversationListRef"
diff --git a/src/components/layout/session/SessionAnalysisHeader.vue b/src/components/layout/session/SessionAnalysisHeader.vue
index ba6362a6..d2b97e32 100644
--- a/src/components/layout/session/SessionAnalysisHeader.vue
+++ b/src/components/layout/session/SessionAnalysisHeader.vue
@@ -105,12 +105,13 @@ const navigationItems = computed(() =>
       <CaptureButton v-else-if="showSessionActions" color="gray" />
     </template>
 
-    <div class="mt-3 flex flex-col items-stretch gap-2 sm:flex-row sm:items-center sm:justify-between sm:gap-3">
+    <div
+      class="mt-3 flex flex-col items-stretch gap-2 sm:min-h-8 sm:flex-row sm:items-center sm:justify-between sm:gap-3"
+    >
       <PageTabs v-model="activeTab" class="min-w-0 shrink" :items="navigationItems" />
       <!-- 不使用时间范围的一级 Tab 不挂载筛选器，避免发起无关查询。 -->
-      <div class="max-w-full overflow-x-auto scrollbar-hide">
+      <div v-if="timeSelectVisible" class="max-w-full overflow-x-auto scrollbar-hide">
         <TimeSelect
-          v-if="timeSelectVisible"
           v-model="timeRangeValue"
           :session-id="currentSessionId ?? undefined"
           :initial-state="initialTimeState"
diff --git a/src/composables/useSessionAnalysisPageBase.test.ts b/src/composables/useSessionAnalysisPageBase.test.ts
index d82973cf..f9ab5c30 100644
--- a/src/composables/useSessionAnalysisPageBase.test.ts
+++ b/src/composables/useSessionAnalysisPageBase.test.ts
@@ -240,3 +240,64 @@ test('session loading coordinates required data, missing ranges, and non-analysi
   assert.equal(page.memberActivity.value[0]?.name, 'session-four')
   assert.equal(page.isLoading.value, false)
 })
+
+test('returning to insights reuses analytics for the unchanged session and time range', async (t) => {
+  await t.mock.module('@/utils', {
+    namedExports: {
+      formatLocalizedDate: () => '',
+    },
+  })
+  const { useSessionAnalysisPageBase } = await import('./useSessionAnalysisPageBase')
+
+  let analysisLoadCount = 0
+  registerAdapter('data', {
+    getSession: async () => ({ id: 'session-one' }),
+    getMemberActivity: async () => [createMember('session-one')],
+    getHourlyActivity: async () => [],
+    getDailyActivity: async () => [],
+    getMessageTypeDistribution: async () => {
+      analysisLoadCount++
+      return []
+    },
+  } as unknown as DataAdapter)
+
+  t.mock.method(console, 'warn', () => undefined)
+  const scope = effectScope()
+  t.after(() => scope.stop())
+  const route = reactive({ params: { id: 'session-one' }, query: {} }) as unknown as RouteLocationNormalizedLoaded
+  const router = { replace: async () => undefined } as unknown as Router
+  const currentSessionId = ref<string | null>('session-one')
+  const page = scope.run(() =>
+    useSessionAnalysisPageBase({
+      route,
+      router,
+      currentSessionId,
+      selectSession: () => undefined,
+      defaultTab: 'ai-chat',
+      validTabIds: ['insights', 'ai-chat'],
+    })
+  )!
+
+  page.timeRangeValue.value = {
+    startTs: 1,
+    endTs: 2,
+    displayLabel: 'test',
+    isFullRange: false,
+    state: { mode: 'custom', customStart: '1970-01-01', customEnd: '1970-01-01' },
+  }
+  await nextTick()
+
+  page.activeTab.value = 'insights'
+  await flushPromises()
+
+  assert.equal(analysisLoadCount, 1)
+  assert.equal(page.isLoading.value, false)
+
+  page.activeTab.value = 'ai-chat'
+  await nextTick()
+  page.activeTab.value = 'insights'
+  await flushPromises()
+
+  assert.equal(analysisLoadCount, 1)
+  assert.equal(page.isLoading.value, false)
+})
diff --git a/src/composables/useSessionAnalysisPageBase.ts b/src/composables/useSessionAnalysisPageBase.ts
index acb5cc73..dd7bc412 100644
--- a/src/composables/useSessionAnalysisPageBase.ts
+++ b/src/composables/useSessionAnalysisPageBase.ts
@@ -41,6 +41,14 @@ export function useSessionAnalysisPageBase(options: UseSessionAnalysisPageBaseOp
   let analysisLoadVersion = 0
   let baseDataReady = false
   let analysisDataReady = false
+  let loadedAnalysisScopeKey: string | null = null
+
+  function getAnalysisScopeKey(): string | null {
+    const sessionId = currentSessionId.value
+    if (!sessionId) return null
+    const filter = timeFilter.value
+    return filter ? `${sessionId}:${filter.startTs}:${filter.endTs}` : `${sessionId}:all`
+  }
 
   function finishSessionSwitchIfReady() {
     if (!isSessionSwitching.value || !baseDataReady) return
@@ -96,6 +104,7 @@ export function useSessionAnalysisPageBase(options: UseSessionAnalysisPageBaseOp
     if (!sessionId) return
 
     const loadVersion = ++analysisLoadVersion
+    const analysisScopeKey = getAnalysisScopeKey()
     if (!activeTabUsesOverviewAnalytics.value) {
       isLoading.value = false
       analysisDataReady = true
@@ -123,6 +132,7 @@ export function useSessionAnalysisPageBase(options: UseSessionAnalysisPageBaseOp
       hourlyActivity.value = hourly
       dailyActivity.value = daily
       messageTypes.value = types
+      loadedAnalysisScopeKey = analysisScopeKey
     } catch (error) {
       if (loadVersion === analysisLoadVersion) {
         console.error('加载分析数据失败:', error)
@@ -178,6 +188,14 @@ export function useSessionAnalysisPageBase(options: UseSessionAnalysisPageBaseOp
       return
     }
 
+    const analysisScopeKey = getAnalysisScopeKey()
+    if (analysisScopeKey && analysisScopeKey === loadedAnalysisScopeKey) {
+      isLoading.value = false
+      analysisDataReady = true
+      finishSessionSwitchIfReady()
+      return
+    }
+
     isLoading.value = true
     if (currentSessionId.value && timeRangeValue.value) void loadAnalysisData()
   })
@@ -201,6 +219,7 @@ export function useSessionAnalysisPageBase(options: UseSessionAnalysisPageBaseOp
     currentSessionId,
     () => {
       analysisLoadVersion++
+      loadedAnalysisScopeKey = null
       resetTimeRange()
       baseDataReady = false
       analysisDataReady = !activeTabUsesTimeRange.value
diff --git a/src/pages/group-chat/index.vue b/src/pages/group-chat/index.vue
index 1835f5cc..9f1950ef 100644
--- a/src/pages/group-chat/index.vue
+++ b/src/pages/group-chat/index.vue
@@ -87,9 +87,6 @@ const {
 
 provide('session-switch-loading', isSessionSwitching)
 
-const isAIChatRestoring = ref(activeTab.value === 'ai-chat' && typeof route.query.aiChatId === 'string')
-const showSessionLoading = computed(() => isSessionSwitching.value || isAIChatRestoring.value)
-
 // 当前筛选后的消息总数
 const filteredMessageCount = computed(() => {
   return memberActivity.value.reduce((sum, m) => sum + m.messageCount, 0)
@@ -104,7 +101,7 @@ const filteredMemberCount = computed(() => {
 <template>
   <div class="relative flex h-full flex-col dark:bg-page-dark" style="padding-top: var(--titlebar-area-height)">
     <div
-      v-if="showSessionLoading"
+      v-if="isSessionSwitching"
       data-testid="group-chat-switch-loading"
       class="absolute inset-0 z-20 flex cursor-wait items-center justify-center bg-page-bg dark:bg-page-dark"
       :style="{ paddingTop: 'var(--titlebar-area-height)' }"
@@ -138,7 +135,7 @@ const filteredMemberCount = computed(() => {
       <!-- Tab Content -->
       <div class="relative flex-1 overflow-y-auto">
         <!-- Loading Overlay -->
-        <LoadingState v-if="isLoading && !showSessionLoading" variant="overlay" :text="t('common.loading')" />
+        <LoadingState v-if="isLoading && !isSessionSwitching" variant="overlay" :text="t('common.loading')" />
 
         <div class="h-full">
           <Transition name="tab-slide" mode="out-in">
@@ -168,7 +165,6 @@ const filteredMemberCount = computed(() => {
               :session-id="currentSessionId!"
               :session-name="session.name"
               chat-type="group"
-              @restore-loading-change="isAIChatRestoring = $event"
             />
             <MemoryTab
               v-else-if="activeTab === 'memory'"
@@ -269,8 +265,7 @@ const filteredMemberCount = computed(() => {
 </template>
 
 <style scoped>
-.tab-slide-enter-active,
-.tab-slide-leave-active {
+.tab-slide-enter-active {
   transition:
     opacity 0.2s ease,
     transform 0.2s ease;
@@ -280,9 +275,4 @@ const filteredMemberCount = computed(() => {
   opacity: 0;
   transform: translateY(10px);
 }
-
-.tab-slide-leave-to {
-  opacity: 0;
-  transform: translateY(-10px);
-}
 </style>
diff --git a/src/pages/insight/index.vue b/src/pages/insight/index.vue
index f4f36506..acce4d87 100644
--- a/src/pages/insight/index.vue
+++ b/src/pages/insight/index.vue
@@ -101,7 +101,7 @@ onBeforeUnmount(() => {
     >
       <PageTabs
         v-if="navigationItems.length > 0"
-        class="mt-3 pb-1.5"
+        class="mt-3 min-h-[38px] pb-1.5"
         :model-value="activeSubpage"
         :items="navigationItems"
         :aria-label="t('insight.tabs.nav')"
diff --git a/src/pages/private-chat/index.vue b/src/pages/private-chat/index.vue
index 3d5ef915..4b688025 100644
--- a/src/pages/private-chat/index.vue
+++ b/src/pages/private-chat/index.vue
@@ -83,9 +83,6 @@ const {
 
 provide('session-switch-loading', isSessionSwitching)
 
-const isAIChatRestoring = ref(activeTab.value === 'ai-chat' && typeof route.query.aiChatId === 'string')
-const showSessionLoading = computed(() => isSessionSwitching.value || isAIChatRestoring.value)
-
 // 当前筛选后的消息总数
 const filteredMessageCount = computed(() => {
   return memberActivity.value.reduce((sum, m) => sum + m.messageCount, 0)
@@ -126,7 +123,7 @@ const otherMemberAvatar = computed(() => {
 <template>
   <div class="relative flex h-full flex-col dark:bg-page-dark" style="padding-top: var(--titlebar-area-height)">
     <div
-      v-if="showSessionLoading"
+      v-if="isSessionSwitching"
       data-testid="private-chat-switch-loading"
       class="absolute inset-0 z-20 flex cursor-wait items-center justify-center bg-page-bg dark:bg-page-dark"
       :style="{ paddingTop: 'var(--titlebar-area-height)' }"
@@ -159,7 +156,7 @@ const otherMemberAvatar = computed(() => {
       <!-- Tab Content -->
       <div class="relative flex-1 overflow-y-auto">
         <!-- Loading Overlay -->
-        <LoadingState v-if="isLoading && !showSessionLoading" variant="overlay" :text="t('common.loading')" />
+        <LoadingState v-if="isLoading && !isSessionSwitching" variant="overlay" :text="t('common.loading')" />
 
         <div class="h-full">
           <Transition name="tab-slide" mode="out-in">
@@ -183,7 +180,6 @@ const otherMemberAvatar = computed(() => {
               :session-id="currentSessionId!"
               :session-name="session.name"
               chat-type="private"
-              @restore-loading-change="isAIChatRestoring = $event"
             />
             <MemoryTab
               v-else-if="activeTab === 'memory'"
@@ -281,8 +277,7 @@ const otherMemberAvatar = computed(() => {
 </template>
 
 <style scoped>
-.tab-slide-enter-active,
-.tab-slide-leave-active {
+.tab-slide-enter-active {
   transition:
     opacity 0.2s ease,
     transform 0.2s ease;
@@ -292,9 +287,4 @@ const otherMemberAvatar = computed(() => {
   opacity: 0;
   transform: translateY(10px);
 }
-
-.tab-slide-leave-to {
-  opacity: 0;
-  transform: translateY(-10px);
-}
 </style>