diff --git a/nova/api/ec2/cloud.py b/nova/api/ec2/cloud.py
index 31fd563f6d18..e04b5f1133e5 100644
--- a/nova/api/ec2/cloud.py
+++ b/nova/api/ec2/cloud.py
@@ -172,7 +172,7 @@ def _format_block_device_mapping(bdm):
                     ('deleteOnTermination', 'delete_on_termination'))
         ebs = {}
         for name, k in ebs_keys:
-            if k in bdm:
+            if bdm.get(k) is not None:
                 if k == 'snapshot_id':
                     ebs[name] = ec2utils.id_to_ec2_snap_id(bdm[k])
                 elif k == 'volume_id':
diff --git a/nova/tests/api/ec2/test_cloud.py b/nova/tests/api/ec2/test_cloud.py
index db8a7177d819..d9ff15e2826f 100644
--- a/nova/tests/api/ec2/test_cloud.py
+++ b/nova/tests/api/ec2/test_cloud.py
@@ -1491,7 +1491,8 @@ class CloudTestCase(test.TestCase):
 
         mappings2 = [{'device': '/dev/sda1', 'virtual': 'root'}]
         block_device_mapping2 = [{'device_name': '/dev/sdb1',
-                'snapshot_id': 'ccec42a2-c220-4806-b762-6b12fbb592e7'}]
+                'snapshot_id': 'ccec42a2-c220-4806-b762-6b12fbb592e7',
+                'volume_id': None}]
         image2 = {
             'id': '76fa36fc-c930-4bf3-8c8a-ea2a2420deb6',
             'name': 'fake_name',