diff --git a/raven/utils/json.py b/raven/utils/json.py
index 8599e246b..654f01902 100644
--- a/raven/utils/json.py
+++ b/raven/utils/json.py
@@ -30,6 +30,8 @@ def default(self, obj):
             return obj.strftime('%Y-%m-%dT%H:%M:%SZ')
         elif isinstance(obj, (set, frozenset)):
             return list(obj)
+        elif isinstance(obj, bytes):
+            return obj.decode('utf-8', errors='replace')
         return super(BetterJSONEncoder, self).default(obj)