diff --git a/lower-constraints.txt b/lower-constraints.txt
index 19e8201..0f028a0 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -35,7 +35,6 @@ kombu==4.0.0
 linecache2==1.0.0
 MarkupSafe==1.0
 mccabe==0.2.1
-mock==2.0.0
 monotonic==0.6
 mox3==0.20.0
 msgpack-python==0.4.0
diff --git a/osc_lib/tests/cli/test_identity.py b/osc_lib/tests/cli/test_identity.py
index c1de255..fa5e802 100644
--- a/osc_lib/tests/cli/test_identity.py
+++ b/osc_lib/tests/cli/test_identity.py
@@ -11,8 +11,8 @@
 #   under the License.
 
 import argparse
+from unittest import mock
 
-import mock
 from openstack import exceptions
 from openstack.identity.v3 import project
 import testtools
diff --git a/osc_lib/tests/command/test_command.py b/osc_lib/tests/command/test_command.py
index a9e171c..59d9efd 100644
--- a/osc_lib/tests/command/test_command.py
+++ b/osc_lib/tests/command/test_command.py
@@ -12,7 +12,7 @@
 #   License for the specific language governing permissions and limitations
 #   under the License.
 
-import mock
+from unittest import mock
 
 from osc_lib.command import command
 from osc_lib import exceptions
diff --git a/osc_lib/tests/command/test_commandmanager.py b/osc_lib/tests/command/test_commandmanager.py
index 137a64f..9d10ad6 100644
--- a/osc_lib/tests/command/test_commandmanager.py
+++ b/osc_lib/tests/command/test_commandmanager.py
@@ -13,7 +13,7 @@
 #   under the License.
 #
 
-import mock
+from unittest import mock
 
 from osc_lib.command import commandmanager
 from osc_lib.tests import utils
diff --git a/osc_lib/tests/fakes.py b/osc_lib/tests/fakes.py
index c30a693..7a11133 100644
--- a/osc_lib/tests/fakes.py
+++ b/osc_lib/tests/fakes.py
@@ -13,9 +13,9 @@
 #   under the License.
 #
 
-import mock
 import six
 import sys
+from unittest import mock
 
 from keystoneauth1 import fixture
 
diff --git a/osc_lib/tests/test_clientmanager.py b/osc_lib/tests/test_clientmanager.py
index 0f32fbe..5a10a37 100644
--- a/osc_lib/tests/test_clientmanager.py
+++ b/osc_lib/tests/test_clientmanager.py
@@ -14,7 +14,7 @@
 #
 
 import copy
-import mock
+from unittest import mock
 
 from keystoneauth1.access import service_catalog
 from keystoneauth1 import exceptions as ksa_exceptions
diff --git a/osc_lib/tests/test_logs.py b/osc_lib/tests/test_logs.py
index 03df2d7..e4ebdb4 100644
--- a/osc_lib/tests/test_logs.py
+++ b/osc_lib/tests/test_logs.py
@@ -11,8 +11,9 @@
 #   under the License.
 #
 
+from unittest import mock
+
 import logging
-import mock
 
 from osc_lib import logs
 from osc_lib.tests import utils
diff --git a/osc_lib/tests/test_shell.py b/osc_lib/tests/test_shell.py
index 7f5dce9..743032c 100644
--- a/osc_lib/tests/test_shell.py
+++ b/osc_lib/tests/test_shell.py
@@ -14,10 +14,10 @@
 #
 
 import copy
-import mock
 import os
 import sys
 import testtools
+from unittest import mock
 
 from osc_lib import shell
 from osc_lib.tests import utils
diff --git a/osc_lib/tests/utils/__init__.py b/osc_lib/tests/utils/__init__.py
index 5cc6a7c..239adfa 100644
--- a/osc_lib/tests/utils/__init__.py
+++ b/osc_lib/tests/utils/__init__.py
@@ -17,8 +17,8 @@
 import contextlib
 import copy
 import json as jsonutils
-import mock
 import os
+from unittest import mock
 
 from cliff import columns as cliff_columns
 import fixtures
diff --git a/osc_lib/tests/utils/test_tags.py b/osc_lib/tests/utils/test_tags.py
index 6b75aab..87f7380 100644
--- a/osc_lib/tests/utils/test_tags.py
+++ b/osc_lib/tests/utils/test_tags.py
@@ -13,7 +13,7 @@
 #   under the License.
 
 import argparse
-import mock
+from unittest import mock
 
 from osc_lib.tests import utils as test_utils
 from osc_lib.utils import tags
diff --git a/osc_lib/tests/utils/test_utils.py b/osc_lib/tests/utils/test_utils.py
index a396537..45b85a9 100644
--- a/osc_lib/tests/utils/test_utils.py
+++ b/osc_lib/tests/utils/test_utils.py
@@ -15,10 +15,10 @@
 
 import six
 import time
+from unittest import mock
 import uuid
 
 from cliff import columns as cliff_columns
-import mock
 
 from osc_lib.cli import format_columns
 from osc_lib import exceptions
diff --git a/test-requirements.txt b/test-requirements.txt
index b324c83..2aab805 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -5,7 +5,6 @@ hacking>=3.0,<3.1.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
-mock>=2.0.0 # BSD
 oslotest>=3.2.0 # Apache-2.0
 requests-mock>=1.1.0 # Apache-2.0
 sphinx!=1.6.6,>=1.6.2 # BSD