diff --git a/superset/views/core.py b/superset/views/core.py
index af2cabe669b5..95ba394b346c 100755
--- a/superset/views/core.py
+++ b/superset/views/core.py
@@ -2172,7 +2172,9 @@ def results_exec(  # pylint: disable=too-many-return-statements
             obj = apply_display_max_row_limit(obj, rows)
 
         return json_success(
-            json.dumps(obj, default=utils.json_iso_dttm_ser, ignore_nan=True)
+            json.dumps(
+                obj, default=utils.json_iso_dttm_ser, ignore_nan=True, encoding=None
+            )
         )
 
     @has_access_api