A door stop, including: a top member, being fixed to the bottom of a door, the top member including a vertically movable bolt, and a spring, for lifting the bolt in relation to the door; and a bottom member, being fixed to the floor, for being disposed below the door at the stopping disposition thereof, wherein the bolt and the bottom member are characterized in bolting by magnetic attraction therebetween, being stronger than the lifting of the bolt by the spring, thereby the bolt does not protrude below the bottom of the door at the non-bolted state, thereby not requiring a gap between the door bottom and the floor.