A spoke receiving hole extends through a flange formed on a rim so as to incline by a predetermined angle in a radial direction with respect to a line perpendicular to a wheel center plane. A head of a spoke seats on a seating surface provided on one side surface of the spoke receiving hole in contact at a region I on the side closer to a rim body, and a head straight portion of the spoke contacts with an edge portion K of an opening on the side distant from the rim body to which a hole portion directly opens on the side opposite from the seating surface of the spoke receiving hole.