diff --git a/Gemfile b/Gemfile
index 488efa0b..5425c9eb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
-source 'http://rubygems.org'
+source 'https://rubygems.org'
 
 # Specify gem dependencies in active_model_serializers.gemspec
 gemspec