diff --git a/requirements.txt b/requirements.txt
index 1cdc591..2fc5503 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -123,7 +123,7 @@ sphinxcontrib-serializinghtml==1.1.4
 terminado==0.8.3
 testpath==0.4.4
 toml==0.10.1
-tornado==6.0.4
+tornado==6.5.5
 tqdm==4.48.2
 traitlets==4.3.3
 twine==3.2.0