diff --git a/tox.ini b/tox.ini
index 3ed5ebbb..80e0067a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -24,7 +24,7 @@ commands =
 [testenv:functional]
 setenv = OS_TEST_PATH=./neutron_dynamic_routing/tests/functional
 commands =
-  python setup.py testr --slowest --testr-args='{posargs}'
+  ostestr --slowest '{posargs}'
 
 [testenv:api]
 sitepackages=True
@@ -33,7 +33,7 @@ setenv =
  OS_TESTR_CONCURRENCY=1
  TEMPEST_CONFIG_DIR={env:TEMPEST_CONFIG_DIR:/opt/stack/tempest/etc}
 commands =
-  python setup.py testr --slowest --testr-args='{posargs}'
+  ostestr --slowest '{posargs}'
 
 [testenv:dsvm-functional]
 setenv =