diff --git a/heat/engine/resources/ceilometer/alarm.py b/heat/engine/resources/ceilometer/alarm.py
index 0751f012bb..e250dc060c 100644
--- a/heat/engine/resources/ceilometer/alarm.py
+++ b/heat/engine/resources/ceilometer/alarm.py
@@ -221,6 +221,11 @@ class CeilometerAlarm(resource.Resource):
 
         kwargs = actions_to_urls(stack, properties)
         kwargs['type'] = 'threshold'
+        if kwargs.get(self.METER_NAME) in NOVA_METERS:
+            prefix = 'user_metadata.'
+        else:
+            prefix = 'metering.'
+
         rule = {}
         for field in ['period', 'evaluation_periods', 'threshold',
                       'statistic', 'comparison_operator', 'meter_name']:
@@ -230,11 +235,6 @@ class CeilometerAlarm(resource.Resource):
         mmd = properties.get(self.MATCHING_METADATA) or {}
         query = properties.get(self.QUERY) or []
 
-        if kwargs.get(self.METER_NAME) in NOVA_METERS:
-            prefix = 'user_metadata.'
-        else:
-            prefix = 'metering.'
-
         # make sure the matching_metadata appears in the query like this:
         # {field: metadata.$prefix.x, ...}
         for m_k, m_v in six.iteritems(mmd):
diff --git a/heat/tests/test_ceilometer_alarm.py b/heat/tests/test_ceilometer_alarm.py
index ccb44c04cd..70c00507e9 100644
--- a/heat/tests/test_ceilometer_alarm.py
+++ b/heat/tests/test_ceilometer_alarm.py
@@ -321,6 +321,24 @@ class CeilometerAlarmTest(common.HeatTestCase):
 
         self.m.VerifyAll()
 
+    def test_alarm_metadata_prefix(self):
+        t = template_format.parse(alarm_template)
+        properties = t['Resources']['MEMAlarmHigh']['Properties']
+        # Test for bug/1383521, where meter_name is in NOVA_METERS
+        properties[alarm.CeilometerAlarm.METER_NAME] = 'memory.usage'
+        properties['matching_metadata'] =\
+            {'metadata.user_metadata.groupname': 'foo'}
+
+        self.stack = self.create_stack(template=json.dumps(t))
+
+        rsrc = self.stack['MEMAlarmHigh']
+        rsrc.properties.data = rsrc.cfn_to_ceilometer(self.stack, properties)
+        self.assertIsNone(rsrc.properties.data.get('matching_metadata'))
+        query = rsrc.properties.data['threshold_rule']['query']
+        expected_query = [{'field': u'metadata.user_metadata.groupname',
+                           'value': u'foo', 'op': 'eq'}]
+        self.assertEqual(expected_query, query)
+
     def test_mem_alarm_high_correct_matching_metadata(self):
         t = template_format.parse(alarm_template)
         properties = t['Resources']['MEMAlarmHigh']['Properties']