diff --git a/nova/api/openstack/compute/legacy_v2/contrib/quota_classes.py b/nova/api/openstack/compute/legacy_v2/contrib/quota_classes.py
index 9229a353a2..0df81ef9f1 100644
--- a/nova/api/openstack/compute/legacy_v2/contrib/quota_classes.py
+++ b/nova/api/openstack/compute/legacy_v2/contrib/quota_classes.py
@@ -72,6 +72,13 @@ class QuotaClassSetsController(wsgi.Controller):
     def update(self, req, id, body):
         context = req.environ['nova.context']
         authorize(context)
+        try:
+            utils.check_string_length(id, 'quota_class_name',
+                                      min_length=1, max_length=255)
+        except exception.InvalidInput as e:
+                raise webob.exc.HTTPBadRequest(
+                    explanation=e.format_message())
+
         quota_class = id
         bad_keys = []
 
diff --git a/nova/api/openstack/compute/quota_classes.py b/nova/api/openstack/compute/quota_classes.py
index 3eb3d44008..46d3224e1d 100644
--- a/nova/api/openstack/compute/quota_classes.py
+++ b/nova/api/openstack/compute/quota_classes.py
@@ -14,6 +14,7 @@
 #    under the License.
 
 import six
+import webob
 
 from nova.api.openstack.compute.schemas import quota_classes
 from nova.api.openstack import extensions
@@ -22,6 +23,7 @@ from nova.api import validation
 from nova import db
 from nova import exception
 from nova import quota
+from nova import utils
 
 
 QUOTAS = quota.QUOTAS
@@ -67,11 +69,18 @@ class QuotaClassSetsController(wsgi.Controller):
         values = QUOTAS.get_class_quotas(context, id)
         return self._format_quota_set(id, values)
 
-    @extensions.expected_errors(())
+    @extensions.expected_errors(400)
     @validation.schema(quota_classes.update)
     def update(self, req, id, body):
         context = req.environ['nova.context']
         authorize(context, action='update', target={'quota_class': id})
+        try:
+            utils.check_string_length(id, 'quota_class_name',
+                                      min_length=1, max_length=255)
+        except exception.InvalidInput as e:
+            raise webob.exc.HTTPBadRequest(
+                explanation=e.format_message())
+
         quota_class = id
 
         for key, value in six.iteritems(body['quota_class_set']):
diff --git a/nova/tests/unit/api/openstack/compute/contrib/test_quota_classes.py b/nova/tests/unit/api/openstack/compute/contrib/test_quota_classes.py
index 92eb8f6396..9295f820f1 100644
--- a/nova/tests/unit/api/openstack/compute/contrib/test_quota_classes.py
+++ b/nova/tests/unit/api/openstack/compute/contrib/test_quota_classes.py
@@ -114,6 +114,12 @@ class QuotaClassSetsTestV21(test.TestCase):
         self.assertRaises(self.validation_error, self.controller.update,
                           self.req, 'test_class', body=body)
 
+    def test_quotas_update_with_long_quota_class_name(self):
+        name = 'a' * 256
+        body = {'quota_class_set': {'instances': 10}}
+        self.assertRaises(webob.exc.HTTPBadRequest, self.controller.update,
+                          self.req, name, body=body)
+
     def test_quotas_update_with_non_integer(self):
         body = {'quota_class_set': {'instances': "abc"}}
         self.assertRaises(self.validation_error, self.controller.update,