Abstract: A door lock guard attachment for use with a door frame and a door provided with a lock having a movable bolt. The lock guard attachment comprises a one piece, elongate L-shaped member having a mounting flange for attachment to either the door or the door frame, and an integral, abuttment flange for abutting a stop rail on the door frame. The inner face of the mounting flange has a plurality of longitudinally and laterally disposed inwardly projecting teeth for impeding the passage of a burglary tool between the door and the door frame.