diff --git a/tests/integration/volume_test.py b/tests/integration/volume_test.py
index 706179ed2..04922ccdc 100644
--- a/tests/integration/volume_test.py
+++ b/tests/integration/volume_test.py
@@ -17,6 +17,7 @@ class VolumeTest(DockerClientTestCase):
                 self.client.remove_volume(volume.full_name)
             except DockerException:
                 pass
+        del self.tmp_volumes
 
     def create_volume(self, name, driver=None, opts=None, external=None):
         if external and isinstance(external, bool):