diff --git a/shadowsocks-csharp/Controller/Logging.cs b/shadowsocks-csharp/Controller/Logging.cs
index f2b170b0..803b0c08 100755
--- a/shadowsocks-csharp/Controller/Logging.cs
+++ b/shadowsocks-csharp/Controller/Logging.cs
@@ -10,7 +10,6 @@ namespace Shadowsocks.Controller
     public class Logging
     {
         public static string LogFilePath;
-        private static DateTime LogFileCreationTime;
 
         public static bool OpenLogFile()
         {