Abstract: An improved trailer lock includes a lock body and a bolt. The lock body includes a housing, a bolt holder, a bushing, a spring, a core and a press dock. The bushing has a latch plate at one side. The latch plate has a bolt wedge trough at one side to form an upper anchor portion and a lower anchor portion at two sides thereof to latch two sides of a latch groove of the bolt during locking to form double sides latching. Thus the trailer lock has a greater locking strength and capability to withstand destruction to prevent damage of the lock body by external forces.