diff --git a/requirements.txt b/requirements.txt
index 6afbe70..e108340 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -176,7 +176,7 @@ tblib==1.3.2
 terminado==0.8.1
 testpath==0.4.2
 toolz==0.9.0
-tornado==6.3.3
+tornado==6.4.1
 tqdm==4.31.1
 traitlets==4.3.2
 unicodecsv==0.14.1