diff --git a/setup.py b/setup.py
index 7c0d10e6a3..e3d189e087 100755
--- a/setup.py
+++ b/setup.py
@@ -98,7 +98,7 @@
     zip_safe = False,
     install_requires = [
         'jinja2',
-        'tornado>=5.0',
+        'tornado>=6.1',
         # pyzmq>=17 is not technically necessary,
         # but hopefully avoids incompatibilities with Tornado 5. April 2018
         'pyzmq>=17',