diff --git a/src/mibew/js/source/widget.js b/src/mibew/js/source/widget.js
index 89e8d2b3..3234cca9 100644
--- a/src/mibew/js/source/widget.js
+++ b/src/mibew/js/source/widget.js
@@ -357,6 +357,12 @@ var Mibew = Mibew || {};
                 + '</h1>';
         }
 
+        // Play sound
+        var sound = document.getElementById('mibew-notification-sound');
+        if (sound) {
+            sound.play();
+        }
+
         // Broadcast message from the thread related with invitation into iframe
         if (threadUrl) {
             popuptext += '<iframe id="mibew-invitation-frame" '
diff --git a/src/mibew/sounds/invite.mp3 b/src/mibew/sounds/invite.mp3
new file mode 100644
index 00000000..baec4638
Binary files /dev/null and b/src/mibew/sounds/invite.mp3 differ
diff --git a/src/mibew/sounds/invite.wav b/src/mibew/sounds/invite.wav
new file mode 100644
index 00000000..9b2415d5
Binary files /dev/null and b/src/mibew/sounds/invite.wav differ