diff --git a/api/setup.py b/api/setup.py
index fe9c2804dc3..7d575dc2ef3 100755
--- a/api/setup.py
+++ b/api/setup.py
@@ -52,7 +52,7 @@ def get_version():
     "writing automated biology lab protocols easy.")
 PACKAGES = find_packages(where='src')
 INSTALL_REQUIRES = [
-    'pyserial==3.4',
+    'pyserial==3.5',
     'numpy>=1.15.1',
     'jsonschema>=3.0.2,<4',
     'aionotify==0.2.0',