diff --git a/container_config_scripts/tests/test_nova_statedir_ownership.py b/container_config_scripts/tests/test_nova_statedir_ownership.py
index 39b4252227..c9bd171224 100644
--- a/container_config_scripts/tests/test_nova_statedir_ownership.py
+++ b/container_config_scripts/tests/test_nova_statedir_ownership.py
@@ -13,8 +13,9 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+from unittest import mock
+
 import contextlib
-import mock
 import six
 import stat
 import sys
diff --git a/lower-constraints.txt b/lower-constraints.txt
index e45d24edcf..d91f79fae6 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -51,7 +51,6 @@ Mako==0.4.0
 MarkupSafe==1.0
 mistral-lib==0.3.0
 mistral==6.0.0
-mock==2.0.0
 monotonic==0.6
 mox3==0.20.0
 msgpack-python==0.4.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 97037839d7..31a7e4d0b3 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -14,7 +14,6 @@ python-subunit>=1.0.0 # Apache-2.0/BSD
 testrepository>=0.0.18 # Apache-2.0/BSD
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
-mock>=2.0.0 # BSD
 oslotest>=3.2.0 # Apache-2.0
 yaql>=1.1.3 # Apache 2.0 License
 ansible-runner>=1.4.2 # Apache
diff --git a/tripleo_heat_templates/tests/test_environment_generator.py b/tripleo_heat_templates/tests/test_environment_generator.py
index da8dc313f3..a81dc4e0ff 100644
--- a/tripleo_heat_templates/tests/test_environment_generator.py
+++ b/tripleo_heat_templates/tests/test_environment_generator.py
@@ -14,8 +14,8 @@
 
 import io
 import tempfile
+from unittest import mock
 
-import mock
 from oslotest import base
 import six
 import testscenarios