diff --git a/test-requirements.txt b/test-requirements.txt
index fbb178570a..5357210248 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -12,5 +12,5 @@ mock>=2.0.0 # BSD
 bashate>=0.5.1 # Apache-2.0
 
 # this is required for the docs build jobs
-sphinx>=1.6.2 # BSD
+sphinx!=1.6.6,>=1.6.2 # BSD
 openstackdocstheme>=1.17.0 # Apache-2.0