Abstract: A magnetic door lock with a time delay option includes an electromagnet mounted on a door frame and an armature mounted on a door. The electromagnet has a pair of laterally spaced slots therein which each have a reed switch therein for monitoring magnetic flux in the electromagnet. When the armature is engaged with the electromagnet, the magnetic flux is at a selected level sufficient to close the reed switches. If, due to tampering or some other reason, the magnetic flux drop does not reach the selected level, at least one of the reed switches will remain open indicating that the armature is not securely engaged with the electromagnet. The door lock also includes separate mounting plates for mounting the electromagnet and armature so that the electromagnet and armature will be properly aligned when mounted. A plunger is provided adjacent the electromagnet for engagement by a block adjacent the armature. When an attempt is made to open the door, the plunger moves thereby sensing the attempt.