To provide a door stopper device which enables an angle of an attractive surface of a magnet to be changed in such a manner as to correspond to an angle of inclination of a stopper plate, and which can keep an attractive force constant.

This door stopper device 1 has a case 2 which is attached to an opening/closing door D. The case 2 comprises the magnet 20 which draws the stopper plate 52 to the side of the case 2 when the door D is opened/closed and the case 2 is positioned above the stopper plate 52 provided on a floor surface F, and a locking portion 8 for inhibiting the opening of the door D by locking the stopper plate 52. The magnet 20 is mounted on a mounting frame 21 which is tiltably provided in the case 2, and the attractive surface 20a of the magnet 20 is inclined in accordance with the inclination of the stopper plate 52.