diff --git a/websocket-sharp/Net/WebHeaderCollection.cs b/websocket-sharp/Net/WebHeaderCollection.cs
index 11c51aa8..0e3f6d3e 100644
--- a/websocket-sharp/Net/WebHeaderCollection.cs
+++ b/websocket-sharp/Net/WebHeaderCollection.cs
@@ -986,11 +986,6 @@ namespace WebSocketSharp.Net
 
     #region Internal Methods
 
-    internal static string Convert (HttpRequestHeader header)
-    {
-      return convert (header.ToString ());
-    }
-
     internal static string Convert (HttpResponseHeader header)
     {
       return convert (header.ToString ());