Abstract: A door hanging retaining alignment plug for a pre-hung door assembly. The pre-hung door assembly including a door having a first bore opening along its free swinging edge for accommodating a retractable bolt or lock and a second bore opening along a face of the door for accommodating a lock box and communicating with the first bore. The retaining alignment plug comprises an elongated strap formed of a flexible material and a cylindrical member projecting longitudinally from one end of the strap and adaptable for seating in the first bore. The strap being adaptable for extending outwardly of the second bore, across the face of the door and the marginal edge of the jamb and across a portion of the jamb face for securing the strap to the jamb face. The strap is secured to the jamb by a suitable nail or staple.