diff --git a/dj_rest_auth/serializers.py b/dj_rest_auth/serializers.py
index 3e0132d..efd455e 100644
--- a/dj_rest_auth/serializers.py
+++ b/dj_rest_auth/serializers.py
@@ -4,6 +4,7 @@ from django.contrib.auth.forms import PasswordResetForm, SetPasswordForm
 from django.contrib.auth.tokens import default_token_generator
 from django.utils.encoding import force_text
 from django.utils.http import urlsafe_base64_decode as uid_decoder
+from django.utils.module_loading import import_string
 from django.utils.translation import ugettext_lazy as _
 from rest_framework import exceptions, serializers
 from rest_framework.exceptions import ValidationError
@@ -145,7 +146,14 @@ class JWTSerializer(serializers.Serializer):
         JWTSerializer. Defining it here to avoid circular imports
         """
         rest_auth_serializers = getattr(settings, 'REST_AUTH_SERIALIZERS', {})
-        JWTUserDetailsSerializer = rest_auth_serializers.get('USER_DETAILS_SERIALIZER', UserDetailsSerializer)
+
+        JWTUserDetailsSerializer = import_string(
+            rest_auth_serializers.get(
+                'USER_DETAILS_SERIALIZER',
+                'dj_rest_auth.serializers.UserDetailsSerializer'
+            )
+        )
+
         user_data = JWTUserDetailsSerializer(obj['user'], context=self.context).data
         return user_data