Vehicle wheel disc and vehicle disc wheel

A vehicle wheel disc to be mounted on a hub of an axle by a plurality of bolts provided to the hub and a plurality of nuts to be threadedly engaged with the plurality of bolts,

• the vehicle wheel disc comprising a mounting portion provided with a plurality of bolt holes through which the plurality of bolts are to be inserted, the mounting portion being adapted to be mounted on the hub by being fastened by the plurality of bolts inserted through the plurality of bolt holes and the plurality of nuts, wherein
• the mounting portion includes a planar plate portion having a pressing surface to be pressed against the hub, and a plurality of nut support portions protruding from the planar plate portion to a side opposite to the pressing surface in an axial direction of the vehicle wheel disc, and having an annular shape as viewed from the axial direction,
• each of the bolt holes penetrates each of the nut support portions in the axial direction,
• each of the nut support portions includes a bulging portion curving to bulge outward in a radial direction of each of the nut support portions, at least one protruding portion disposed adjacent to the bulging portion in a circumferential direction of each of the nut support portions, and protruding in a thickness direction of the bulging portion of each of the nut support portions with respect to the bulging portion, and a nut bearing surface formed at a center portion of each of the nut support portions, and
• the bulging portion and the at least one protruding portion are formed outside of the nut bearing surface in the radial direction of each of the nut support portions.