diff --git a/requirements.txt b/requirements.txt
index abbcf3c..f199ca2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -216,7 +216,7 @@ terminado==0.8.1
 testpath==0.3.1
 tinycss2==0.6.1
 toolz==0.9.0
-tornado==5.0.1
+tornado==6.3.3
 tqdm==4.23.2
 traitlets==4.3.2
 typing==3.6.4