A motor-vehicle wheel structure comprises a wheel rim and a wheel disk having a circumferential border bent and welded within the rim, and a central portion bearing a circumferential series of holes for engagement of bolts for fixing the wheel to the wheel support. The central portion is connected to the circumferential border of the disk by an intermediate annular portion having in cross section an arched configuration projecting outwards. Welded on the outer face of the wheel disk is an auxiliary disk having a substantially plane conformation, the outer border of which is welded to the main disk substantially in a position corresponding to the apex of the aforesaid projecting annular portion. The auxiliary disk integrates tubular columns that project from the inner face of the auxiliary disk and have their ends welded to the central portion of the main disk so that they are co-axial to the holes for the fixing bolts.