diff --git a/tox.ini b/tox.ini
index 0f7ec5e8096..45f8968fd48 100644
--- a/tox.ini
+++ b/tox.ini
@@ -18,11 +18,13 @@ commands =
 # mode. To do this define the TRACE_FAILONLY environmental variable.
 
 [testenv:api]
+basepython = python2.7
 setenv = OS_TEST_PATH=./neutron/tests/api
          TEMPEST_CONFIG_DIR={env:TEMPEST_CONFIG_DIR:/opt/stack/tempest/etc}
          OS_TEST_API_WITH_REST=1
 
 [testenv:functional]
+basepython = python2.7
 setenv = OS_TEST_PATH=./neutron/tests/functional
          OS_TEST_TIMEOUT=180
 deps =
@@ -30,6 +32,7 @@ deps =
   -r{toxinidir}/neutron/tests/functional/requirements.txt
 
 [testenv:dsvm-functional]
+basepython = python2.7
 setenv = OS_TEST_PATH=./neutron/tests/functional
          OS_SUDO_TESTING=1
          OS_ROOTWRAP_CMD=sudo {envdir}/bin/neutron-rootwrap {envdir}/etc/neutron/rootwrap.conf
@@ -63,6 +66,7 @@ sitepackages = True
 downloadcache = ~/cache/pip
 
 [testenv:pep8]
+basepython = python2.7
 deps =
   {[testenv]deps}
   pylint
@@ -79,6 +83,7 @@ whitelist_externals =
   bash
 
 [testenv:cover]
+basepython = python2.7
 commands =
   python setup.py testr --coverage --testr-args='{posargs}'