Abstract: A piston door stop comprising a hollow first shaft, a hollow second shaft which partially contains said first shaft, a spring, a base screw, and a rubber cap. The spring extends through the bore of both shafts. The first shaft, second shaft, spring, and the rubber cap are coaxial. The door stopper is screwed into a wall via the base screw such that a bottom surface of a head of the base screw is in contact with the surface of said wall. A swung door first hits the rubber cap which covers the second shaft. The force is then transmitted to the spring which is contained within the two shafts, such that the second shaft moves along the first shaft towards the wall, compressing the spring which is contained within both shafts; thus causing the spring to absorb all of the energy transmitted from the swung door.