diff --git a/tox.ini b/tox.ini
index 229dc2f1fe8..9f7d991a5ed 100644
--- a/tox.ini
+++ b/tox.ini
@@ -27,6 +27,7 @@ setenv = VIRTUAL_ENV={envdir}
 
 [testenv:api]
 setenv = OS_TEST_PATH=./neutron/tests/api
+         TEMPEST_CONFIG_DIR={env:TEMPEST_CONFIG_DIR:/opt/stack/tempest/etc}
 
 [testenv:functional]
 setenv = OS_TEST_PATH=./neutron/tests/functional