PURPOSE: To facilitate the opening/closing operation of a door by forming a locking member to be a slide-lock member having a hook which is allowed to slide to a closing position locked by a locking member, and oscillated to be hook-engaged with the locking member by a riding edge part on a casing side.

CONSTITUTION: A slide-lock member 9 having a hook of a lock 5 to cooperate with a holding projection 6 and an energizing plate piece 8 comprises a locking member head 10 to be projected from a lock casing G and a locking member tail part 11 which is connected to the head 10 and located in the casing, and the head 10 is provided with a hook 12 on the face side of the locking member. The hook 12 is engaged with a recess 7 of a locking member 3 when a door 2 is closed. This constitution provides the lock which is simple in structure and very easy in operation.