diff --git a/test-requirements.txt b/test-requirements.txt
index a5c1c11..79b6b30 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -22,7 +22,7 @@ openstack.nose-plugin>=0.7 # Apache-2.0
 oslosphinx>=4.7.0 # Apache-2.0
 reno>=1.8.0 # Apache-2.0
 selenium>=2.50.1 # Apache-2.0
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
 testtools>=1.4.0 # MIT
 # This also needs xvfb library installed on your OS
 xvfbwrapper>=0.1.3 #license: MIT