Abstract: A door brace alarm apparatus for resisting movement of a door and for providing a sound alarm when such movement of the door is attempted. Two slideably connected shaft members are adjustable for angular placement between the door knob and the floor. A bifurcated yoke and a floor support retain the door brace alarm in position by contact with the door knob and floor. A pivotally mounted alarm housing connected to one of the shaft members houses an alarm retainer which provides for extension adjustment by threaded cooperation with a cavity in the alarm housing. The alarm retainer houses the sound generator and adjusts to position the sound generator in juxtaposition with the door so that it will emit an alarm sound upon impact by the door.