diff --git a/dvc/state_file.py b/dvc/state_file.py
index 3b5b75b9d..028894185 100644
--- a/dvc/state_file.py
+++ b/dvc/state_file.py
@@ -264,7 +264,7 @@ class CacheStateFile(object):
     MAGIC = 'DVC-Cache-State'
     VERSION = '0.1'
 
-    PARAM_MD5 = 'Md5'
+    PARAM_MD5 = StateFile.PARAM_MD5
 
     def __init__(self, data_item, md5=None):
         self.data_item = data_item