diff --git a/requirements-dev.txt b/requirements-dev.txt
index a7c2dff1ed717d38826bbafe1e9606cd401b1c1e..80cb14161346dc50024d156f6baf79bb888044d1 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -7,5 +7,6 @@ pytest-pylint
 pytest-watch
 sphinx
 sphinx-autoapi
+sphinx_rtd_theme
 sphinxcontrib-versioning
 yapf>=0.29.0