diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 25ad4ca53e..ab588bcca7 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -909,7 +909,7 @@ class PositiveSmallIntegerField(IntegerField):
     def get_manipulator_field_objs(self):
         return [oldforms.PositiveSmallIntegerField]
 
-class SlugField(Field):
+class SlugField(CharField):
     def __init__(self, *args, **kwargs):
         kwargs['max_length'] = kwargs.get('max_length', 50)
         kwargs.setdefault('validator_list', []).append(validators.isSlug)