An anchor bolt which is inserted into and fixed in an attachment bore provided in a wall surface comprising: a rod; a taper member connected to the rod; three or five abutment parts fitted over the taper member; and an elastically deformable bridge connecting the abutment parts with each other; wherein the taper member has a central axis, a cross section orthogonal to the central axis in a form of an equilateral triangle or pentagon, and three or five inclined surfaces at respective sides of the triangle or pentagon, the inclined surfaces being inclined closer to the central axis of the taper member toward a base end of the anchor bolt, wherein the number of the abutment parts is the same as the number of the inclined surfaces of the taper member, and each of the abutment part has an inner surface which is inclined closer to the central axis of the taper member toward the base end and which abuts the inclined surface of the taper member, wherein in a state in which the taper member and the abutment parts are inserted into the attachment bore from a tip side of the anchor bolt, when only the taper member is moved toward an opening of the attachment bore, the abutment parts are pushed toward an inner peripheral surface of the attachment bore due to the inclined surfaces of the taper member, and outer peripheral surfaces of the abutment parts are pressed against the inner peripheral surface of the attachment bore so that the abutment parts are fixed in the attachment bore wherein the bridge includes a main body disposed on a tip side of the rod and connecting parts extending from an edge of the main body and connected to tips of the abutment parts, characterized in that the connecting parts extend from the edge of the main body toward the base end in an outward and inclined direction with respect to the rod and are then bent toward the rod at longitudinally intermediate portions of the connecting parts, and the connecting parts have respective free ends connected to the tips of the corresponding abutment parts, and wherein when the anchor bolt is pushed into the attachment bore, the intermediate portions of the connecting parts are pressed by an edge of an opening or the inner peripheral surface of the attachment bore to be elastically deformed so that the intermediate portions of the connecting parts and the abutment parts are pressed against the inner peripheral surface of the attachment bore due to an elastic recovery force. a rod; a taper member connected to the rod; three or five abutment parts fitted over the taper member; and an elastically deformable bridge connecting the abutment parts with each other; wherein the taper member has a central axis, a cross section orthogonal to the central axis in a form of an equilateral triangle or pentagon, and three or five inclined surfaces at respective sides of the triangle or pentagon, the inclined surfaces being inclined closer to the central axis of the taper member toward a base end of the anchor bolt, wherein the number of the abutment parts is the same as the number of the inclined surfaces of the taper member, and each of the abutment part has an inner surface which is inclined closer to the central axis of the taper member toward the base end and which abuts the inclined surface of the taper member, wherein in a state in which the taper member and the abutment parts are inserted into the attachment bore from a tip side of the anchor bolt, when only the taper member is moved toward an opening of the attachment bore, the abutment parts are pushed toward an inner peripheral surface of the attachment bore due to the inclined surfaces of the taper member, and outer peripheral surfaces of the abutment parts are pressed against the inner peripheral surface of the attachment bore so that the abutment parts are fixed in the attachment bore wherein the bridge includes a main body disposed on a tip side of the rod and connecting parts extending from an edge of the main body and connected to tips of the abutment parts, characterized in that the connecting parts extend from the edge of the main body toward the base end in an outward and inclined direction with respect to the rod and are then bent toward the rod at longitudinally intermediate portions of the connecting parts, and the connecting parts have respective free ends connected to the tips of the corresponding abutment parts, and wherein when the anchor bolt is pushed into the attachment bore, the intermediate portions of the connecting parts are pressed by an edge of an opening or the inner peripheral surface of the attachment bore to be elastically deformed so that the intermediate portions of the connecting parts and the abutment parts are pressed against the inner peripheral surface of the attachment bore due to an elastic recovery force.