Disclosed is a plug; the plug comprises a force application part, a slide block, a lock catch and a locking elastic piece, wherein the slide block is slidably mounted in an insulator and is connectedwith the force application part; the lock catch is mounted on the insulator in a rotationally connected mode, and is matched with a clamping groove in a socket for locking the plug and the socket; thelocking elastic piece is connected with the slide block and can rotate to enable the lock catch to be separated from the clamping groove to unlock the plug and the socket when the slide block moves;the locking elastic piece extends downwards to form an elastic claw II which abuts against the insulator and is used for performing automatic reset of the locking elastic piece, the slide block and the force application piece after unlocking is completed. When the connector adopting the plug is used for unlocking the plug and the socket, only the force application part needs to be pulled, the locking elastic piece is pushed by the slide block to rotate to enable the lock catch to be separated from the clamping groove, so that the operation is convenient; and in addition, the plug can be quickly inserted and plugged in the small space, and the product is convenient to maintain.