diff --git a/tempest/api/volume/test_volumes_extend.py b/tempest/api/volume/test_volumes_extend.py
index ac9a9c7..c3f44e2 100644
--- a/tempest/api/volume/test_volumes_extend.py
+++ b/tempest/api/volume/test_volumes_extend.py
@@ -32,7 +32,7 @@
     @decorators.idempotent_id('9a36df71-a257-43a5-9555-dc7c88e66e0e')
     def test_volume_extend(self):
         # Extend Volume Test.
-        volume = self.create_volume(image_ref=self.image_ref)
+        volume = self.create_volume(imageRef=self.image_ref)
         extend_size = volume['size'] * 2
         self.volumes_client.extend_volume(volume['id'],
                                           new_size=extend_size)
diff --git a/tempest/api/volume/test_volumes_snapshots.py b/tempest/api/volume/test_volumes_snapshots.py
index 1855386..72e7290 100644
--- a/tempest/api/volume/test_volumes_snapshots.py
+++ b/tempest/api/volume/test_volumes_snapshots.py
@@ -44,7 +44,7 @@
         server = self.create_server()
         # NOTE(zhufl) Here we create volume from self.image_ref for adding
         # coverage for "creating snapshot from non-blank volume".
-        volume = self.create_volume(image_ref=self.image_ref)
+        volume = self.create_volume(imageRef=self.image_ref)
         self.attach_volume(server['id'], volume['id'])
 
         # Snapshot a volume which attached to an instance with force=False