diff --git a/test-requirements.txt b/test-requirements.txt
index 1c9e3b4245..c30101f286 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,6 +4,6 @@
 PyYAML>=3.10.0 # MIT
 Jinja2!=2.9.0,!=2.9.1,!=2.9.2,!=2.9.3,!=2.9.4,>=2.8 # BSD License (3 clause)
 six>=1.9.0 # MIT
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
 oslosphinx>=4.7.0 # Apache-2.0
 reno>=1.8.0 # Apache-2.0