diff --git a/rest_framework/authtoken/models.py b/rest_framework/authtoken/models.py
index fa1f4ea61..3b8bffeb8 100644
--- a/rest_framework/authtoken/models.py
+++ b/rest_framework/authtoken/models.py
@@ -7,7 +7,7 @@ from django import VERSION
 
 if VERSION[:2] in ((1, 5,),):
     from django.conf import settings
-    if hasattr(settings, AUTH_USER_MODEL):
+    if hasattr(settings, 'AUTH_USER_MODEL'):
         user_model = settings.AUTH_USER_MODEL
     else:
         from django.contrib.auth.models import User as user_model