diff --git a/fe/src/com/baidu/palo/mysql/MysqlServer.java b/fe/src/com/baidu/palo/mysql/MysqlServer.java
index 6dddde84035a47..2e90f7021c904b 100644
--- a/fe/src/com/baidu/palo/mysql/MysqlServer.java
+++ b/fe/src/com/baidu/palo/mysql/MysqlServer.java
@@ -40,7 +40,7 @@ public class MysqlServer {
     private ConnectScheduler scheduler = null;
     // used to accept connect request from client
     private Thread listener;
-    private boolean running;
+    private volatile boolean running;
 
     public MysqlServer(int port, ConnectScheduler scheduler) {
         this.port = port;