To provide a bearing device for wheels, capable of increasing the hardness of the periphery of the bearing surface of the hub bolt hole of a flange for mounting wheels being a part desired for strength and fatigue strength under high stress and cyclic stress in a limited manner, and capable of suppressing the degradation of productivity caused by an increase in the number of manufacturing steps.

A parent material part of a hub 14 having the flange for mounting wheels 17 has a standard structure formed through hot forging process from a steel material. A part 30 comprising the bearing surface 18b of the hub bolt hole 18 on the side of the flange 17 for mounting the wheels and the periphery of the bearing surface 18b is made in a non-standard structure. The non-standard structure is obtained by laser hardening.