diff --git a/test-requirements.txt b/test-requirements.txt
index bb1307f..208032f 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -28,11 +28,6 @@ oslo.utils<=3.41.0;python_version<'3.6'
 requests>=2.18.4
 charms.reactive
 
-# Newer mock seems to have some syntax which is newer than python3.5 (e.g.
-# f'{something}'
-mock>=1.2,<4.0.0; python_version < '3.6'
-mock>=1.2; python_version >= '3.6'
-
 nose>=1.3.7
 coverage>=3.6
 git+https://github.com/openstack/charms.openstack.git#egg=charms.openstack
diff --git a/unit_tests/__init__.py b/unit_tests/__init__.py
index c1dc275..b69ab59 100644
--- a/unit_tests/__init__.py
+++ b/unit_tests/__init__.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+import unittest.mock as mock
 import sys
 
 
diff --git a/unit_tests/test_gnocchi_handlers.py b/unit_tests/test_gnocchi_handlers.py
index 0cda5e9..e2e77ad 100644
--- a/unit_tests/test_gnocchi_handlers.py
+++ b/unit_tests/test_gnocchi_handlers.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+from unittest import mock
 
 import charms_openstack.test_utils as test_utils