diff --git a/requirements.txt b/requirements.txt
index 1b26122..c6830be 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 coverage==4.5.1
-enum34==1.1.6
+enum34==1.1.9
 futures==3.2.0; python_version < '3.0'
 googleapis-common-protos==1.5.3
 grpcio==1.8.4