diff --git a/common/lib/xmodule/xmodule/course_module.py b/common/lib/xmodule/xmodule/course_module.py
index ae3c01f639..a1549185b1 100644
--- a/common/lib/xmodule/xmodule/course_module.py
+++ b/common/lib/xmodule/xmodule/course_module.py
@@ -202,7 +202,7 @@ class CourseDescriptor(SequenceDescriptor):
         # Try to load grading policy
         paths = ['grading_policy.json']
         if policy_dir:
-            paths = [policy_dir + 'grading_policy.json'] + paths
+            paths = [policy_dir + '/grading_policy.json'] + paths
 
         policy = json.loads(cls.read_grading_policy(paths, system))