A ball screw device, comprising: a screw shaft having a spiral groove on an outer surface; a nut having on an inner surface a spiral groove corresponding to the groove of the screw shaft and screwed with the screw shaft; a plurality of balls loaded in a rollable fashion along a spiral raceway between both of the grooves (11, 21); and a rotational part having both ends fitted to respective recirculation holes of a pair of recirculation holes formed in a flat surface, which is bored on a circumferential side surface of the nut, in a direction approximately orthogonal to a centerline of the nut, so as to create a ball recirculating path for leading the plurality of balls rolling along the spiral raceway to the outside of the nut from one recirculation hole of the pair of recirculation holes, and returning the plurality of balls to the spiral raceway from the other recirculation hole, wherein the rotational part comprises a pair of legs that include a tongue portion for scooping up the balls that roll along the spiral raceway on the ends of the legs in a direction approximately tangential to the spiral raceway and that have both ends fitted to the recirculation holes of the nut, and a main body connecting the pair of legs, and further comprises a first divided face for dividing the pair of legs along the ball recirculating path, and a second divided face for dividing the main body along the ball recirculating path; characterized in that the second divided face is formed such that an upper divided face and a lower divided face of the ball recirculating path intersect with each other when viewed from the flat surface of the nut. a screw shaft having a spiral groove on an outer surface; a nut having on an inner surface a spiral groove corresponding to the groove of the screw shaft and screwed with the screw shaft; a plurality of balls loaded in a rollable fashion along a spiral raceway between both of the grooves (11, 21); and a rotational part having both ends fitted to respective recirculation holes of a pair of recirculation holes formed in a flat surface, which is bored on a circumferential side surface of the nut, in a direction approximately orthogonal to a centerline of the nut, so as to create a ball recirculating path for leading the plurality of balls rolling along the spiral raceway to the outside of the nut from one recirculation hole of the pair of recirculation holes, and returning the plurality of balls to the spiral raceway from the other recirculation hole, wherein the rotational part comprises a pair of legs that include a tongue portion for scooping up the balls that roll along the spiral raceway on the ends of the legs in a direction approximately tangential to the spiral raceway and that have both ends fitted to the recirculation holes of the nut, and a main body connecting the pair of legs, and further comprises a first divided face for dividing the pair of legs along the ball recirculating path, and a second divided face for dividing the main body along the ball recirculating path; characterized in that the second divided face is formed such that an upper divided face and a lower divided face of the ball recirculating path intersect with each other when viewed from the flat surface of the nut.