diff --git a/app/src/main/java/com/stand/standapp/UpdateManager.kt b/app/src/main/java/com/stand/standapp/UpdateManager.kt
index 29e0961..99a549f 100644
--- a/app/src/main/java/com/stand/standapp/UpdateManager.kt
+++ b/app/src/main/java/com/stand/standapp/UpdateManager.kt
@@ -34,11 +34,13 @@ class UpdateManager(private val context: Context) {
     private val fileName = "StandApp_Update.apk"
 
     /**
-     * 获取应用缓存目录下的临时文件 URI，避免申请外部存储权限
+     * 获取应用外部专属下载目录下的文件 URI，避免申请外部存储权限的同时确保安装包能被系统安装器读取
      */
     private fun getCacheFileUri(): Uri {
-        val cacheDir = context.externalCacheDir ?: context.cacheDir
-        val file = File(cacheDir, fileName)
+        val dir = context.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS)
+            ?: context.externalCacheDir
+            ?: context.cacheDir
+        val file = File(dir, fileName)
         if (file.exists()) {
             file.delete()
         }