diff --git a/samples/api-client/manager/requirements.txt b/samples/api-client/manager/requirements.txt
index 5bee1597..9e7afcd8 100644
--- a/samples/api-client/manager/requirements.txt
+++ b/samples/api-client/manager/requirements.txt
@@ -1,6 +1,6 @@
 cryptography==2.9.2
 flaky==3.6.1
-google-api-python-client==1.8.4
+google-api-python-client==1.9.1
 google-auth-httplib2==0.0.3
 google-auth==1.16.0
 google-cloud-iot==1.0.0