To detect deterioration of regulation fastening force due to looseness of a hub bolt by regulating the fastening force of the hub bolt, which fastens a wheel, and maintaining the practical fastening force even if fitting (permanent set) is generated in the wheel.

In this double-wheel fastening structure, a wheel is fastened through an elastic body (a plate spring 3), and a ring 4 for detecting the bending quantity of the elastic body (the plate spring 3) is arranged with a preset gap G between an end surface of a nut 2 and the ring 4 when no load is applied to the plate spring 3. When the gap G is reduced, finally, to zero by fastening and the fastening force achieves the regulation fastening force, the ring 4 can not be turned by fingers.