diff --git a/APKInstaller/Resource.cs b/APKInstaller/Resource.cs
index d1dd1d2..bf3cbc1 100644
--- a/APKInstaller/Resource.cs
+++ b/APKInstaller/Resource.cs
@@ -82,14 +82,44 @@ public static void Cleanup(object sender, CancelEventArgs cancelEventArgs)
         {
             if (OtherInstanceExists()) return;
 
+            Message.Add("クリーンアップ中...");
+
             while (IsLocked(TempDirectory))
             {
                 Thread.Sleep(500);
             }
 
-            Directory.Delete(TempDirectory, true);
-            Message.Add("完了");
-            Thread.Sleep(1000);
+            var directoryIsEmpty = true;
+            var files = Directory.GetFiles(TempDirectory);
+            foreach (var file in files)
+            {
+                var tryout = 0;
+                while (IsLocked(file) && tryout < 5)
+                {
+                    ++tryout;
+                    Thread.Sleep(200);
+                }
+
+                if (tryout >= 5)
+                {
+                    directoryIsEmpty = false;
+                    continue;
+                }
+
+                File.Delete(file);
+            }
+
+            if (directoryIsEmpty)
+            {
+                Directory.Delete(TempDirectory, true);
+                Message.Add("完了");
+                Thread.Sleep(1000);
+            }
+            else
+            {
+                Message.Add("他のアプリケーションが通信機能を使用しているため、クリーンアップをスキップしました。");
+                Thread.Sleep(4000);
+            }
         }
 
         public static bool OtherInstanceExists()