diff --git a/nova/image/glance.py b/nova/image/glance.py
index f12c0ca546b0..a90647b2f2fa 100644
--- a/nova/image/glance.py
+++ b/nova/image/glance.py
@@ -965,7 +965,9 @@ def _extract_attributes(image, include_locations=False):
                 output[attr] = getattr(image, attr, None)
         # NOTE(mdorman): 'size' attribute must not be 'None', so use 0 instead
         elif attr == 'size':
-            output[attr] = getattr(image, attr) or 0
+            # NOTE(mriedem): A snapshot image may not have the size attribute
+            # set so default to 0.
+            output[attr] = getattr(image, attr, 0) or 0
         else:
             # NOTE(xarses): Anything that is caught with the default value
             # will result in an additional lookup to glance for said attr.
diff --git a/nova/tests/unit/image/test_glance.py b/nova/tests/unit/image/test_glance.py
index e0c8391f562a..6158c48903ae 100644
--- a/nova/tests/unit/image/test_glance.py
+++ b/nova/tests/unit/image/test_glance.py
@@ -2412,6 +2412,25 @@ class TestExtractAttributes(test.NoDBTestCase):
             image_v2, include_locations=False)
         self.assertEqual(v1_output, v2_output)
 
+    @mock.patch.object(schemas, 'Schema', side_effect=FakeSchema)
+    def test_extract_image_attributes_empty_images_no_size(self,
+                                                           mocked_schema):
+        image_v1_dict = dict(image_fixtures['empty_image_v1'])
+        # pop the size attribute since it might not be set on a snapshot image
+        image_v1_dict.pop('size')
+        image_v2 = ImageV2(image_fixtures['empty_image_v2'])
+
+        image_v1 = collections.namedtuple('_', image_v1_dict.keys())(
+            **image_v1_dict)
+
+        self.flags(use_glance_v1=True, group='glance')
+        v1_output = glance._translate_from_glance(
+            image_v1, include_locations=False)
+        self.flags(use_glance_v1=False, group='glance')
+        v2_output = glance._translate_from_glance(
+            image_v2, include_locations=False)
+        self.assertEqual(v1_output, v2_output)
+
     @mock.patch.object(schemas, 'Schema', side_effect=FakeSchema)
     def test_extract_image_attributes_active_images_custom_prop(
             self, mocked_schema):