diff --git a/requirements.txt b/requirements.txt
index b4b0f831..d9279233 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
 PyYAML==3.12
 six==1.10.0
-pyserial==3.3
+pyserial==3.5
 tornado==4.5.1