diff --git a/django_common/db_fields.py b/django_common/db_fields.py
index f844a08..a923180 100644
--- a/django_common/db_fields.py
+++ b/django_common/db_fields.py
@@ -49,7 +49,7 @@ def get_prep_value(self, value):
         if value == "":
             return None
 
-        if isinstance(value, dict):
+        if isinstance(value, (dict, list)):
             value = json.dumps(value, cls=DjangoJSONEncoder)
 
         return value