diff --git a/doc/source/contributor/unit_tests.rst b/doc/source/contributor/unit_tests.rst
index c86891f51..387ecb00b 100644
--- a/doc/source/contributor/unit_tests.rst
+++ b/doc/source/contributor/unit_tests.rst
@@ -27,13 +27,13 @@ options and what the test run does by default.
 Running a subset of tests using tox
 -----------------------------------
 One common activity is to just run a single test, you can do this with tox
-simply by specifying to just run py27 or py35 tests against a single test::
+simply by specifying to just run py3 tests against a single test::
 
-    tox -epy27 -- -n cinderclient.tests.unit.v2.test_volumes.VolumesTest.test_attach
+    tox -e py3 -- -n cinderclient.tests.unit.v2.test_volumes.VolumesTest.test_attach
 
 Or all tests in the test_volumes.py file::
 
-    tox -epy27 -- -n cinderclient.tests.unit.v2.test_volumes
+    tox -e py3 -- -n cinderclient.tests.unit.v2.test_volumes
 
 For more information on these options and how to run tests, please see the
 `stestr documentation <https://stestr.readthedocs.io/en/latest/index.html>`_.