diff --git a/websocket-sharp/WebSocketFrame.cs b/websocket-sharp/WebSocketFrame.cs
index a3c7ac90..4dc91f4c 100644
--- a/websocket-sharp/WebSocketFrame.cs
+++ b/websocket-sharp/WebSocketFrame.cs
@@ -630,7 +630,7 @@ Extended Payload Length: {7}
       }
 
       if (len > PayloadData.MaxLength) {
-        var msg = "A frame has too long payload data length.";
+        var msg = "A frame has too long payload length.";
         throw new WebSocketException (CloseStatusCode.TooBig, msg);
       }