diff --git a/app/src/main/java/org/mercury_im/messenger/ui/chat/ChatActivity.java b/app/src/main/java/org/mercury_im/messenger/ui/chat/ChatActivity.java
index e3e1dcc..e6bf8f4 100644
--- a/app/src/main/java/org/mercury_im/messenger/ui/chat/ChatActivity.java
+++ b/app/src/main/java/org/mercury_im/messenger/ui/chat/ChatActivity.java
@@ -89,6 +89,9 @@ public class ChatActivity extends AppCompatActivity
         viewModel.getContactDisplayName().observe(this,
                 name -> getSupportActionBar().setTitle(name));
 
+        viewModel.getContact().observe(this, contactModel ->
+                getSupportActionBar().setSubtitle(contactModel.getEntity().getJid().asUnescapedString()));
+
         viewModel.getMessages().observe(this, messageModels -> {
             recyclerViewAdapter.updateMessages(messageModels);
             recyclerView.scrollToPosition(messageModels.size() - 1);