diff --git a/requirements.txt b/requirements.txt
index 4cfb0227..12699ea4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ numpy>=1.7.1
 pymc==2.3.4
 pyzmq>=13.1.0
 scipy>=0.12.0
-tornado>=3.0.2
+tornado>=6.4.2
 wsgiref>=0.1.2
 praw>=2.0.0
 jinja2