diff --git a/beat/web/backend/models.py b/beat/web/backend/models.py
index 86eb9971636abcbd61a7e465f05a491cb5e9c3ca..2c4265e4c29be6cb08fe941c7ec99c7bda02cab9 100644
--- a/beat/web/backend/models.py
+++ b/beat/web/backend/models.py
@@ -171,7 +171,7 @@ def _cleanup_zombies():
     '''Cleans-up eventual zombie subprocesses launched by the worker'''
 
     for child in psutil.Process().children(recursive=True):
-        if child.status == psutil.STATUS_ZOMBIE:
+        if child.status() == psutil.STATUS_ZOMBIE:
             child.wait()