diff --git a/tox.ini b/tox.ini
index c320bb5ec5..a6e2ae0969 100644
--- a/tox.ini
+++ b/tox.ini
@@ -34,6 +34,10 @@ setenv =
     OS_TEST_DBAPI_ADMIN_CONNECTION=mysql+pymysql://openstack_citest:openstack_citest@localhost/;postgresql://openstack_citest:openstack_citest@localhost/postgres;sqlite://
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements-py3.txt
+       # NOTE(viktors): simplegeneric supposed to be installed by WSME, but for
+       #                a some reasons it was missed in py3 env.
+       # TODO(viktors): Remove this workaround, when WSME fix this issue.
+       simplegeneric
 
 [testenv:pep8]
 commands =