diff --git a/lib/galaxy/queue_worker.py b/lib/galaxy/queue_worker.py
index d13b1666c50..24fcba5e83e 100644
--- a/lib/galaxy/queue_worker.py
+++ b/lib/galaxy/queue_worker.py
@@ -410,3 +410,4 @@ class GalaxyQueueWorker(ConsumerProducerMixin, threading.Thread):
 
     def shutdown(self):
         self.should_stop = True
+        self.join()