diff --git a/awx/api/views/__init__.py b/awx/api/views/__init__.py
index 6663f05b1d..35576c913a 100644
--- a/awx/api/views/__init__.py
+++ b/awx/api/views/__init__.py
@@ -3265,7 +3265,7 @@ class WorkflowJobRelaunch(GenericAPIView):
             jt = obj.job_template
             if not jt:
                 raise ParseError(_('Cannot relaunch slice workflow job orphaned from job template.'))
-            elif not jt.inventory or min(jt.inventory.hosts.count(), jt.job_slice_count) != obj.workflow_nodes.count():
+            elif not obj.inventory or min(obj.inventory.hosts.count(), jt.job_slice_count) != obj.workflow_nodes.count():
                 raise ParseError(_('Cannot relaunch sliced workflow job after slice count has changed.'))
         new_workflow_job = obj.create_relaunch_workflow_job()
         new_workflow_job.signal_start()