Abstract: The present invention discloses a trailer connector sleeve lock, comprising a lock cover, a lock tongue piece and a lock hole plate, wherein the lock hole plate is rotatably installed on the lock cover and is provided with a lock hole, and the lock hole plate rotates to the lock cover to serve as the side wall of the lock cover, they are spliced together to form a sleeve lock structure, wherein an opening is arranged above the sleeve lock structure, and the opening is smaller than the size of the lock tongue piece, wherein the lock tongue piece is provided with a lock tongue and is clamped in the sleeve lock structure, wherein the lock tongue extends out of the lock hole and is fixed through an additional lock.