diff --git a/README.en.md b/README.en.md
index e92edae..b76190e 100644
--- a/README.en.md
+++ b/README.en.md
@@ -123,6 +123,8 @@ services:
       - ENABLE_TEMP_UPLOAD=true
       - ADMIN_API_KEY=your-secret-key
       - SUBSET_CACHE_MAX_SIZE=10485760
+      # Temp font retention (seconds), auto-deleted if unused. Default: 10800 (3h)
+      - TEMP_RETENTION_SECONDS=10800
 ```
 
 ## API Reference
diff --git a/README.md b/README.md
index 6391770..244fe5b 100644
--- a/README.md
+++ b/README.md
@@ -123,6 +123,8 @@ services:
       - ENABLE_TEMP_UPLOAD=true
       - ADMIN_API_KEY=your-secret-key
       - SUBSET_CACHE_MAX_SIZE=10485760
+      # 临时字体保留时限（秒），超时未使用自动删除，默认 10800（3小时）
+      - TEMP_RETENTION_SECONDS=10800
 ```
 
 ## API
diff --git a/backend/config.ts b/backend/config.ts
index 687e4c7..dbb4f90 100644
--- a/backend/config.ts
+++ b/backend/config.ts
@@ -15,8 +15,8 @@ export const tempMaxFiles = parseInt(env.TEMP_MAX_FILES ?? "10", 10) || 10;
 /** 临时上传目录总体积上限（字节），默认 200MB */
 export const tempMaxTotalSize = parseInt(env.TEMP_MAX_TOTAL_SIZE ?? `${200 * 1024 * 1024}`, 10) || 200 * 1024 * 1024;
 
-/** 临时字体保留时限（小时），超过后若无人使用则自动删除 */
-export const tempRetentionHours = parseFloat(env.TEMP_RETENTION_HOURS ?? "3") || 3;
+/** 临时字体保留时限（秒），超过后若无人使用则自动删除 */
+export const tempRetentionSeconds = parseInt(env.TEMP_RETENTION_SECONDS ?? "10800", 10) || 10800;
 
 /** 字体裁剪结果内存缓存容量上限（字节），默认 10MB */
 export const subsetCacheMaxSize = parseInt(env.SUBSET_CACHE_MAX_SIZE ?? `${10 * 1024 * 1024}`, 10) || 10 * 1024 * 1024;
diff --git a/backend/routes/config.ts b/backend/routes/config.ts
index fd0b0dc..f533bef 100644
--- a/backend/routes/config.ts
+++ b/backend/routes/config.ts
@@ -1,5 +1,5 @@
 import { jsonResponse } from "../shared";
-import { enableTempUpload, adminApiKey, tempRetentionHours } from "../config";
+import { enableTempUpload, adminApiKey, tempRetentionSeconds } from "../config";
 
 /** GET /api/config — 返回公开配置 */
 export async function handleGetConfig(req: Request, _res: Response) {
@@ -9,8 +9,8 @@ export async function handleGetConfig(req: Request, _res: Response) {
       enableTempUpload,
       adminUploadEnabled: !!adminApiKey,
       supportedOutTypes: ["woff2", "ttf"],
-      /** 临时字体保留时限（小时） */
-      tempRetentionHours,
+      /** 临时字体保留时限（秒） */
+      tempRetentionSeconds,
     }),
   };
 }
diff --git a/backend/temp_cleaner.ts b/backend/temp_cleaner.ts
index ae85fc2..c79075e 100644
--- a/backend/temp_cleaner.ts
+++ b/backend/temp_cleaner.ts
@@ -7,7 +7,7 @@
  * 清理周期 = 保留时限的一半（最少 5 分钟），避免过于频繁的扫描。
  */
 import { readdir, stat, unlink, path_join } from "./interface";
-import { tempRetentionHours } from "./config";
+import { tempRetentionSeconds } from "./config";
 
 /** 临时字体目录 */
 const TEMP_DIR = "font/temp";
@@ -33,7 +33,7 @@ export function markFontUsed(fontPath: string): void {
  */
 async function cleanOnce(): Promise<void> {
   const now = Date.now();
-  const retentionMs = tempRetentionHours * 3600_000;
+  const retentionMs = tempRetentionSeconds * 1000;
 
   let entries: Array<{ name: string; isFile: () => boolean }>;
   try {
@@ -64,7 +64,7 @@ async function cleanOnce(): Promise<void> {
 }
 
 /** 清理周期：保留时限的一半，最少 5 分钟 */
-const CLEAN_INTERVAL = Math.max(tempRetentionHours * 1800_000, 300_000);
+const CLEAN_INTERVAL = Math.max(tempRetentionSeconds * 500, 300_000);
 
 /**
  * 启动定时清理器。
@@ -72,7 +72,7 @@ const CLEAN_INTERVAL = Math.max(tempRetentionHours * 1800_000, 300_000);
  */
 export function startTempCleaner(): void {
   const intervalSec = Math.round(CLEAN_INTERVAL / 1000);
-  console.log(`[temp-cleaner] 启动，保留时限 ${tempRetentionHours}h，清理周期 ${intervalSec}s`);
+  console.log(`[temp-cleaner] 启动，保留时限 ${tempRetentionSeconds}s，清理周期 ${intervalSec}s`);
 
   /** 首次延迟 60 秒 */
   setTimeout(() => {
diff --git a/src/UploadSection.vue b/src/UploadSection.vue
index 6da611c..26bc866 100644
--- a/src/UploadSection.vue
+++ b/src/UploadSection.vue
@@ -82,8 +82,14 @@ function onFileSelect(e: Event, target: ReturnType<typeof useUpload>) {
       <div style="font-size: 14px; font-weight: 500; margin-bottom: 4px">{{ t('guestUpload') }}</div>
       <div style="font-size: 12px; color: #999; margin-bottom: 12px">
         {{ t('guestUploadDesc') }}
-        <span v-if="config.tempRetentionHours" style="color: #1677ff">
-          （保留时限 {{ config.tempRetentionHours }} 小时）
+        <span v-if="config.tempRetentionSeconds" style="color: #1677ff">
+          （保留时限 {{
+            config.tempRetentionSeconds >= 3600
+              ? Math.round(config.tempRetentionSeconds / 3600 * 10) / 10 + ' 小时'
+              : config.tempRetentionSeconds >= 60
+                ? Math.round(config.tempRetentionSeconds / 60) + ' 分钟'
+                : config.tempRetentionSeconds + ' 秒'
+          }}）
         </span>
       </div>
       <div style="display: flex; gap: 8px; align-items: center">
diff --git a/src/api.ts b/src/api.ts
index 8ec52f1..0a08a83 100644
--- a/src/api.ts
+++ b/src/api.ts
@@ -9,8 +9,8 @@ export interface ServerConfig {
   enableTempUpload: boolean;
   adminUploadEnabled: boolean;
   supportedOutTypes: ("woff2" | "ttf")[];
-  /** 临时字体保留时限（小时） */
-  tempRetentionHours?: number;
+  /** 临时字体保留时限（秒） */
+  tempRetentionSeconds?: number;
 }
 
 export interface UploadResult {