diff --git a/lower-constraints.txt b/lower-constraints.txt
index 26e8b73..ec32af3 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -37,7 +37,7 @@ requestsexceptions==1.2.0
 semantic-version==2.3.1
 six==1.10.0
 snowballstemmer==1.2.1
-Sphinx==1.6.5
+Sphinx==1.6.2
 sphinxcontrib-websupport==1.0.1
 stevedore==1.20.0
 stestr==1.0.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 834ce26..856557a 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -6,7 +6,8 @@ hacking<0.12,>=0.11.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=1.0.0 # Apache-2.0/BSD
-sphinx!=1.6.6,!=1.6.7,>=1.6.5 # 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,>=1.6.2;python_version>='3.4' # BSD
 openstackdocstheme>=1.18.1 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD