To provide a door lock mechanism capable of locking a door at an optional position and maintaining door in a locked state without releasing it even if power failure occurs when door is locked and being comparatively inexpensively manufacturable.

This door lock mechanism uses a self-holding type solenoid 16 and includes such a configuration (a restrained means 28 and a restraining means 30) that prevents rotation of a movable iron core 20 of the self-holding type solenoid.