diff --git a/setup.py b/setup.py
index e3686b0..43afad5 100644
--- a/setup.py
+++ b/setup.py
@@ -13,7 +13,7 @@
 requirements = [
     'click',
     'hyper',
-    'tornado',
+    'tornado==5.1.1',
     'requests',
     'python-dateutil'
 ]
@@ -28,7 +28,7 @@
 
 setup(
     name='avs',
-    version='0.5.4',
+    version='0.5.5',
     description="Alexa Voice Service Python SDK",
     long_description=long_description,
     long_description_content_type='text/markdown',