diff --git a/docs/requirements.txt b/docs/requirements.txt
index 42727833be..372712e29f 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -18,5 +18,5 @@ tensorflow-probability<0.6.0,>=0.5.0
 
 # dev dependencies
 recommonmark
-sphinx
+sphinx==2.4.4
 sphinx_rtd_theme
diff --git a/setup.py b/setup.py
index 23bcf09629..4ef76a4dc0 100644
--- a/setup.py
+++ b/setup.py
@@ -80,7 +80,7 @@
     'recommonmark',
     'rlkit @ https://{}@api.github.com/repos/vitchyr/rlkit/tarball/1d469a509b797ca04a39b8734c1816ca7d108fc8'.format(GARAGE_GH_TOKEN),  # noqa: E501
     'seaborn',
-    'sphinx',
+    'sphinx==2.4.4',
     'sphinx_rtd_theme',
     'yapf==0.28.0',
 ]  # yapf: disable