diff --git a/src/main/java/com/actiontech/dble/net/connection/AbstractConnection.java b/src/main/java/com/actiontech/dble/net/connection/AbstractConnection.java
index 991b28acf..df390c1bf 100644
--- a/src/main/java/com/actiontech/dble/net/connection/AbstractConnection.java
+++ b/src/main/java/com/actiontech/dble/net/connection/AbstractConnection.java
@@ -58,7 +58,7 @@ public abstract class AbstractConnection implements Connection {
     protected long netInBytes;
     protected long netOutBytes;
     protected long lastLargeMessageTime;
-    private int sequenceId = 0;
+    private int extraPartOfBigPacketCount = 0;
 
     protected final ConcurrentLinkedQueue<WriteOutTask> writeQueue = new ConcurrentLinkedQueue<>();
     private final ConcurrentLinkedQueue<byte[]> decompressUnfinishedDataQueue = new ConcurrentLinkedQueue<>();
@@ -99,7 +99,7 @@ public abstract class AbstractConnection implements Connection {
             switch (result.getCode()) {
                 case PART_OF_BIG_PACKET:
 
-                    sequenceId++;
+                    extraPartOfBigPacketCount++;
                     if (!result.isHasMorePacket()) {
                         readReachEnd();
                         dataBuffer.clear();
@@ -133,18 +133,18 @@ public abstract class AbstractConnection implements Connection {
     private void processPacketData(ProtoHandlerResult result) {
         byte[] packetData = result.getPacketData();
         if (packetData != null) {
-            int tmpSequenceId = sequenceId;
+            int tmpCount = extraPartOfBigPacketCount;
             if (!isSupportCompress) {
-                sequenceId = 0;
-                service.handle(new ServiceTask(packetData, service, tmpSequenceId));
+                extraPartOfBigPacketCount = 0;
+                service.handle(new ServiceTask(packetData, service, tmpCount));
             } else {
                 List<byte[]> packs = CompressUtil.decompressMysqlPacket(packetData, decompressUnfinishedDataQueue);
                 if (decompressUnfinishedDataQueue.isEmpty()) {
-                    sequenceId = 0;
+                    extraPartOfBigPacketCount = 0;
                 }
                 for (byte[] pack : packs) {
                     if (pack.length != 0) {
-                        service.handle(new ServiceTask(pack, service, tmpSequenceId++));
+                        service.handle(new ServiceTask(pack, service, tmpCount));
                     }
                 }
             }
diff --git a/src/main/java/com/actiontech/dble/net/service/ServiceTask.java b/src/main/java/com/actiontech/dble/net/service/ServiceTask.java
index 5b9e6ee48..f8eaef2a6 100644
--- a/src/main/java/com/actiontech/dble/net/service/ServiceTask.java
+++ b/src/main/java/com/actiontech/dble/net/service/ServiceTask.java
@@ -1,6 +1,6 @@
 package com.actiontech.dble.net.service;
 
-import javax.annotation.Nullable;
+import java.util.Arrays;
 
 /**
  * Created by szf on 2020/6/18.
@@ -10,13 +10,18 @@ public class ServiceTask {
     private final byte[] orgData;
     private final boolean reuse;
     private final Service service;
-    private Integer sequenceId = null;
+    private int extraPartOfBigPacketCount = 0;
 
-    public ServiceTask(byte[] orgData, Service service, @Nullable Integer sequenceId) {
+    /**
+     * @param orgData
+     * @param service
+     * @param extraPartsOfBigPacketCount if orgData are big packet, it contains some *extra* parts of big packet,you should pass the count.If orgData isn't big packet ,just set 0.
+     */
+    public ServiceTask(byte[] orgData, Service service, int extraPartsOfBigPacketCount) {
         this.orgData = orgData;
         this.service = service;
         this.reuse = false;
-        this.sequenceId = sequenceId;
+        this.extraPartOfBigPacketCount = extraPartsOfBigPacketCount;
     }
 
     public ServiceTask(byte[] orgData, Service service, boolean reuse) {
@@ -37,15 +42,10 @@ public class ServiceTask {
         return reuse;
     }
 
-    public int getSequenceId() {
-        if (sequenceId != null) {
-            return sequenceId;
-        } else {
-            if (orgData == null) {
-                throw new IllegalStateException("can't get Sequence Id from null");
-            }
-            return (orgData[3]);
+    public int getLastSequenceId() {
+        if (orgData == null || orgData.length < 4) {
+            throw new IllegalStateException("can't get Sequence Id from " + Arrays.toString(orgData));
         }
-
+        return (orgData[3]) + extraPartOfBigPacketCount;
     }
 }
diff --git a/src/main/java/com/actiontech/dble/services/FrontendService.java b/src/main/java/com/actiontech/dble/services/FrontendService.java
index 734ba6c44..21fa12868 100644
--- a/src/main/java/com/actiontech/dble/services/FrontendService.java
+++ b/src/main/java/com/actiontech/dble/services/FrontendService.java
@@ -107,7 +107,7 @@ public abstract class FrontendService<T extends UserConfig> extends AbstractServ
         if (executeTask != null) {
             byte[] data = executeTask.getOrgData();
             if (data != null && !executeTask.isReuse()) {
-                this.setPacketId(executeTask.getSequenceId());
+                this.setPacketId(executeTask.getLastSequenceId());
             }
 
             this.handleInnerData(data);
@@ -134,7 +134,7 @@ public abstract class FrontendService<T extends UserConfig> extends AbstractServ
 
     private void taskToPriorityQueue(ServiceTask task) {
         DbleServer.getInstance().getFrontPriorityQueue().offer(task);
-        DbleServer.getInstance().getFrontHandlerQueue().offer(new ServiceTask(null, null, null));
+        DbleServer.getInstance().getFrontHandlerQueue().offer(new ServiceTask(null, null, 0));
     }
 
     @Override