diff --git a/src/requirements.txt b/src/requirements.txt
index 9752a00..9487e7b 100644
--- a/src/requirements.txt
+++ b/src/requirements.txt
@@ -3,7 +3,7 @@ falcon==3.0.0b1
 flower==0.9.2
 gunicorn==19.9.0
 redis==3.2.0
-tornado>=4.2.0,<6.0.0
+tornado>=6.3.3,<6.0.0
 pandas
 datetime
 sklearn