diff --git a/Gemfile b/Gemfile
index 7542bdef4..2c29c462d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,5 +1,5 @@
 source "https://rubygems.org"
 gem 'github-pages', group: :jekyll_plugins
-gem 'html-proofer'
+gem 'html-proofer', "3.17"
 gem 'mdl'
 gem "faraday", "~> 0.17"