diff --git a/lib/rubygems/commands/rebuild_command.rb b/lib/rubygems/commands/rebuild_command.rb
index 9747171e5c..295d3f9c88 100644
--- a/lib/rubygems/commands/rebuild_command.rb
+++ b/lib/rubygems/commands/rebuild_command.rb
@@ -3,6 +3,7 @@
 require "date"
 require "digest"
 require "fileutils"
+require "tmpdir"
 require_relative "../package"
 
 class Gem::Commands::RebuildCommand < Gem::Command
@@ -167,14 +168,10 @@ An example of reproducing a gem build:
   end
 
   def prep_dirs
-    rebuild_dir = File.expand_path("rebuild")
+    rebuild_dir = Dir.mktmpdir("gem_rebuild")
     old_dir = File.join(rebuild_dir, "old")
     new_dir = File.join(rebuild_dir, "new")
 
-    if File.directory?(rebuild_dir)
-      FileUtils.remove_dir(rebuild_dir)
-    end
-
     FileUtils.mkdir_p(old_dir)
     FileUtils.mkdir_p(new_dir)