diff --git a/tox.ini b/tox.ini
index 23b70288a7b..acec80aaecf 100644
--- a/tox.ini
+++ b/tox.ini
@@ -21,6 +21,7 @@ commands =
 
 [testenv:api]
 basepython = python2.7
+passenv = {[testenv]passenv} TEMPEST_CONFIG_DIR
 setenv = {[testenv]setenv}
          OS_TEST_PATH=./neutron/tests/api
          OS_TEST_API_WITH_REST=1