A switch for vehicles, which temporarily holds the screw maintaining reliability, can be easily assembled, and is particularly suited for detecting the opening and closure of doors. An insertion hole is formed in a cylindrical portion of a cover covering the upper surface of a mounting plate and an operation body, the insertion hole extending into a through hole of the mounting plate. A screw is forcibly held in the insertion hole. This prevents an inconvenience of the screw escaping when a shock is given or a force is exerted from the lower side during the transit or while being attached to the vehicle.