diff --git a/requirements-docs.txt b/requirements-docs.txt
index ceb62e6c..8d4750e4 100644
--- a/requirements-docs.txt
+++ b/requirements-docs.txt
@@ -92,7 +92,7 @@ six==1.15.0               # via -r requirements.txt, acme, bcrypt, cryptography,
 snowballstemmer==2.0.0    # via sphinx
 soupsieve==2.0.1          # via -r requirements.txt, beautifulsoup4
 sphinx-rtd-theme==0.5.0   # via -r requirements-docs.in
-sphinx==3.2.1             # via -r requirements-docs.in, sphinx-rtd-theme, sphinxcontrib-httpdomain
+sphinx==3.3.0             # via -r requirements-docs.in, sphinx-rtd-theme, sphinxcontrib-httpdomain
 sphinxcontrib-applehelp==1.0.2  # via sphinx
 sphinxcontrib-devhelp==1.0.2  # via sphinx
 sphinxcontrib-htmlhelp==1.0.3  # via sphinx