diff --git a/lower-constraints.txt b/lower-constraints.txt
index 20610a2ed..bc4fdbbcb 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -18,7 +18,6 @@ idna==2.6
 iso8601==0.1.12
 keystoneauth1==3.4.0
 linecache2==1.0.0
-mock==2.0.0
 monotonic==1.4
 mox3==0.25.0
 msgpack==0.5.6