diff --git a/activerecord/lib/active_record/transactions.rb b/activerecord/lib/active_record/transactions.rb
index 9f4532b3160f56728435b800e5b845407bb8f58d..2c3d99632243c81fab5c141deff3102c8c7e2094 100644
--- a/activerecord/lib/active_record/transactions.rb
+++ b/activerecord/lib/active_record/transactions.rb
@@ -1,5 +1,3 @@
-require 'thread'
-
 module ActiveRecord
   # See ActiveRecord::Transactions::ClassMethods for documentation.
   module Transactions