A ball screw nut includes a nut part and a pulley part integrally molded with the nut part on the outer peripheral side of the nut part and having external teeth. The pulley part has a cylindrical portion extending in an axial direction and facing the nut part in a radial direction, and an extended portion extending radially inward from the cylindrical portion and facing the nut part in the axial direction. A restriction part for restricting relative rotation of the nut part and the pulley part is provided between a facing surface of the extended portion facing the nut part and a facing surface of the nut part facing the extended portion.