diff --git a/doc/requirements.txt b/doc/requirements.txt
index aa9dd6b2..389d628c 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,5 +1,6 @@
 # This is required for the docs build jobs
-sphinx # BSD
+sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7' # BSD
+sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2;python_version>='3.4' # BSD
 openstackdocstheme # Apache-2.0
 
 # This is required for the releasenotes build jobs