diff --git a/clients/cmd/fluentd/docker/Gemfile b/clients/cmd/fluentd/docker/Gemfile
index 1d9635a6e8c5..981d6e701e63 100644
--- a/clients/cmd/fluentd/docker/Gemfile
+++ b/clients/cmd/fluentd/docker/Gemfile
@@ -2,5 +2,5 @@
 
 source 'https://rubygems.org'
 
-gem 'fluentd', '1.14.2'
+gem 'fluentd', '1.15.3'
 gem 'fluent-plugin-multi-format-parser', '~>1.0.0'