diff --git a/monasca_common/rest/utils.py b/monasca_common/rest/utils.py
index 36ae3cd1..43757c17 100644
--- a/monasca_common/rest/utils.py
+++ b/monasca_common/rest/utils.py
@@ -53,7 +53,7 @@ def as_json(data, **kwargs):
 
     data = json.dumps(data, **kwargs)
 
-    return data.encode(ENCODING)
+    return data
 
 
 @_try_catch