diff --git a/requires/installation.txt b/requires/installation.txt
index d450f7f..6dfc681 100644
--- a/requires/installation.txt
+++ b/requires/installation.txt
@@ -1,2 +1,2 @@
 ietfparse>=1.4,<1.5
-tornado>=3.2,<6
+tornado>=5,<6