diff --git a/lib/bundler/setup.rb b/lib/bundler/setup.rb
index ac6a5bf861..0ab582c2a2 100644
--- a/lib/bundler/setup.rb
+++ b/lib/bundler/setup.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+return unless defined?(Gem)
+
 require "bundler/shared_helpers"
 
 if Bundler::SharedHelpers.in_bundle?