diff --git a/DDG4/python/DDSim/DD4hepSimulation.py b/DDG4/python/DDSim/DD4hepSimulation.py
index 0917f7790..18a88fdf9 100644
--- a/DDG4/python/DDSim/DD4hepSimulation.py
+++ b/DDG4/python/DDSim/DD4hepSimulation.py
@@ -357,8 +357,9 @@ def run(self):
          (self.action.stack, DDG4.StackingAction, kernel.stackingAction)]:
       for action_dict in action_list:
         action = DDG4_Action(kernel, action_dict["name"])
-        for parameter, value in action_dict['parameter'].items():
-          setattr(action, parameter, value)
+        if 'parameter' in action_dict.keys():
+          for parameter, value in action_dict['parameter'].items():
+            setattr(action, parameter, value)
         kernel_Action().add(action)
 
     # ----------------------------------------------------------------------------------