In combination with a door, a door jamb and a latch bolt, a door security device for preventing the jimmying of a door latch bolt comprising a strike plate; a barrier plate comprising a base portion, a barrier portion and a hinge providing mechanical connection between said base portion and said barrier portion, the barrier plate designed and configured to conform to and fill the gap formed between the door and the door jamb upon closing the door into the door jamb; and one or more fasteners for installing the door security device into the door jamb.