diff --git a/src/components/analysis/Overview/OverviewIdentityCard.vue b/src/components/analysis/Overview/OverviewIdentityCard.vue
index 6aed2f0..07890b7 100644
--- a/src/components/analysis/Overview/OverviewIdentityCard.vue
+++ b/src/components/analysis/Overview/OverviewIdentityCard.vue
@@ -1,14 +1,23 @@
 <script setup lang="ts">
+import { computed } from 'vue'
 import { useI18n } from 'vue-i18n'
 import type { AnalysisSession } from '@/types/base'
+import { formatDateRange } from '@/utils'
 
 const { t } = useI18n()
 
-defineProps<{
+const props = defineProps<{
   session: AnalysisSession
   totalDurationDays: number
   totalDailyAvgMessages: number
+  timeRange: { start: number; end: number } | null
 }>()
+
+// 聊天记录起止时间（完整范围）
+const fullTimeRangeText = computed(() => {
+  if (!props.timeRange) return ''
+  return formatDateRange(props.timeRange.start, props.timeRange.end, 'YYYY/MM/DD')
+})
 </script>
 
 <template>
@@ -29,6 +38,10 @@ defineProps<{
           {{ session.type === 'private' ? t('privateChat') : t('groupChat') }} ·
           <span class="opacity-80">{{ t('analysisReport') }}</span>
         </p>
+        <!-- 聊天记录起止时间 -->
+        <p v-if="fullTimeRangeText" class="mt-2 text-sm font-medium text-pink-100/90 dark:text-gray-400">
+          {{ fullTimeRangeText }}
+        </p>
       </div>
 
       <div class="mt-8 grid grid-cols-3 gap-6">
diff --git a/src/pages/group-chat/components/OverviewTab.vue b/src/pages/group-chat/components/OverviewTab.vue
index 6a79951..6ac9842 100644
--- a/src/pages/group-chat/components/OverviewTab.vue
+++ b/src/pages/group-chat/components/OverviewTab.vue
@@ -137,6 +137,7 @@ watch(
       :session="session"
       :total-duration-days="totalDurationDays"
       :total-daily-avg-messages="totalDailyAvgMessages"
+      :time-range="timeRange"
     />
 
     <!-- 关键指标卡片 -->
diff --git a/src/pages/private-chat/components/OverviewTab.vue b/src/pages/private-chat/components/OverviewTab.vue
index 9f3e9b4..895a9ba 100644
--- a/src/pages/private-chat/components/OverviewTab.vue
+++ b/src/pages/private-chat/components/OverviewTab.vue
@@ -147,6 +147,7 @@ watch(
       :session="session"
       :total-duration-days="totalDurationDays"
       :total-daily-avg-messages="totalDailyAvgMessages"
+      :time-range="timeRange"
     />
 
     <!-- 双方消息对比 -->
diff --git a/src/utils/dateFormat.ts b/src/utils/dateFormat.ts
index 72955bd..43b1c21 100644
--- a/src/utils/dateFormat.ts
+++ b/src/utils/dateFormat.ts
@@ -81,13 +81,13 @@ export function formatWithDayjs(ts: number, format: string): string {
  * 格式化日期范围（支持自定义格式）
  * @param startTs 开始时间戳（秒）
  * @param endTs 结束时间戳（秒）
- * @param format 日期格式，默认 'YYYY.MM.DD'
+ * @param format 日期格式，默认 'YYYY/MM/DD'
  * @param separator 分隔符，默认 ' - '
  */
 export function formatDateRange(
   startTs: number,
   endTs: number,
-  format: string = 'YYYY.MM.DD',
+  format: string = 'YYYY/MM/DD',
   separator: string = ' - '
 ): string {
   const start = dayjs.unix(startTs).format(format)