diff --git a/websocket-sharp/Net/HttpListenerPrefix.cs b/websocket-sharp/Net/HttpListenerPrefix.cs
index 450aefe4..7484138a 100644
--- a/websocket-sharp/Net/HttpListenerPrefix.cs
+++ b/websocket-sharp/Net/HttpListenerPrefix.cs
@@ -39,7 +39,6 @@
 #endregion
 
 using System;
-using System.Net;
 
 namespace WebSocketSharp.Net
 {