diff --git a/requirements-docs.txt b/requirements-docs.txt
index 20a59b4..8952d7f 100644
--- a/requirements-docs.txt
+++ b/requirements-docs.txt
@@ -62,7 +62,7 @@ sphinxcontrib-qthelp==1.0.3
 sphinxcontrib-serializinghtml==1.1.5
 stack-data==0.3.0
 tinycss2==1.1.1
-tornado==6.2
+tornado==6.4.1
 tqdm==4.64.0
 traitlets==5.3.0
 urllib3==1.26.19