diff --git a/graphql_flask/graphqlview.py b/graphql_flask/graphqlview.py
index d371466..a6ca5d9 100644
--- a/graphql_flask/graphqlview.py
+++ b/graphql_flask/graphqlview.py
@@ -172,4 +172,6 @@ def format_error(error):
 
     @staticmethod
     def get_content_type(request):
-        return request.content_type
+        # We use mimetype here since we don't need the other
+        # information provided by content_type
+        return request.mimetype