diff --git a/broker/src/main/java/io/moquette/persistence/DatabaseStore.java b/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
index 840fefe2..130d6167 100644
--- a/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
+++ b/broker/src/main/java/io/moquette/persistence/DatabaseStore.java
@@ -915,7 +915,7 @@ public class DatabaseStore {
         return false;
     }
 
-    void persistUserMessage(final String userId, final long messageId, final long messageSeq, int type, String target, int line, boolean directing, final int messageContentType) {
+    void persistUserMessage(final String userId, final  String sender, final long messageId, final long messageSeq, int type, String target, int line, boolean directing, final int messageContentType) {
         mScheduler.execute(()->{
             Connection connection = null;
             PreparedStatement statement = null;
@@ -930,7 +930,7 @@ public class DatabaseStore {
                 statement.setString(index++, userId);
                 statement.setLong(index++, messageSeq);
                 statement.setInt(index++, type);
-                statement.setString(index++, target);
+                statement.setString(index++, getPrivateChatUserMessageTarget(type, target, sender));
                 statement.setInt(index++, line);
                 statement.setInt(index++, directing ? 1 :0);
                 statement.setInt(index++, messageContentType);
@@ -946,6 +946,14 @@ public class DatabaseStore {
         });
     }
 
+    String getPrivateChatUserMessageTarget(int conversationType, String target, String userId) {
+        if(conversationType == ProtoConstants.ConversationType.ConversationType_Private) {
+            return target.compareTo(userId) > 0 ? (userId + "|" + target) : (target + "|" + userId);
+        } else {
+            return target;
+        }
+    }
+
     void clearUserMessage(final String userId) {
         mScheduler.execute(()->{
             String tableName = getUserMessageTable(userId);
diff --git a/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java b/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
index 4a7230b4..78f3e491 100755
--- a/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
+++ b/broker/src/main/java/io/moquette/persistence/MemoryMessagesStore.java
@@ -1012,7 +1012,7 @@ public class MemoryMessagesStore implements IMessagesStore {
             mWriteLock.unlock();
         }
 
-        databaseStore.persistUserMessage(user, messageId, messageSeq, conversationType, target, line, directing, messageContentType);
+        databaseStore.persistUserMessage(user, sender, messageId, messageSeq, conversationType, target, line, directing, messageContentType);
         return messageSeq;
     }