diff --git a/lower-constraints.txt b/lower-constraints.txt
index 27085dc417..6706c9a347 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -36,7 +36,7 @@ keystonemiddleware==4.17.0
 linecache2==1.0.0
 lxml==3.4.1
 MarkupSafe==1.0
-mock==2.0
+mock==3.0
 monotonic==1.4
 msgpack==0.5.6
 netaddr==0.7.19
diff --git a/test-requirements.txt b/test-requirements.txt
index 1e77045c9d..b5cf150d6e 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -8,7 +8,7 @@ coverage>=5.0.4 # Apache-2.0
 pytest>=4.6.11  # MIT
 pytest-cov>=2.12.1  # MIT
 stestr>=2.0.0 # Apache-2.0
-mock>=2.0 # BSD
+mock>=3.0 # BSD
 python-swiftclient>=3.2.0
 python-keystoneclient!=2.1.0,>=2.0.0 # Apache-2.0
 boto>=2.32.1