An insert type emergency stop cover with key comprises an emergency stop button, a lock cover and a lock base. The lock base is equipped with a groove. The lock cover is equipped with a bolt. When the emergency stop cover is in the state of locking, the bolt plugs in the groove, and the lock cover and the lock base are buckled together. The emergency stop button has a key. The emergency stop button is equipped with a cam. The front end of the key is equipped with a small groove. The cam is equipped with a small boss. When the key inserts the emergency stop button, the small groove on the key can lock the small boss on the cam. The cam and the lock cover joint. A return spring and the boss of the cam are positioned in the groove of the lock cover. A slope joints with the terminal faces of the boss of the bolt on the cam. The bolt is made to be apart from the groove through the linear movement of the bolt driven by the cam transferred from the key, and the lock cover can not be opened. When no key or other tool is use to make the cam move, as a result, the locking cover can not be opened.