To provide a device for fitting tire-and-wheel assembly to wheel balancer which can correct the static and dynamic upbalances of a tire-and-wheel assembly with high reproducibility by detecting the unbalances with high accuracy.

A hollow truncated cone-shaped centering member 14, a wheel receiving member 13, and a wheel pressing member 15 are provided on the shaft 12 of the main body of a wheel balancer and the disk seating section 13a of the member 13 is provided with a mobile piece 19 having long holes which are elongated in the radial direction and arranged at prescribed intervals in the peripheral direction and projecting sections 19b which can get in and out of the long holes and an elastic member 24 which energizes the piece 19 so that parts of the projecting sections 19b can be protruded from the section 13a. As a wheel is pushed in, the disk section of the wheel comes into contact with the projecting sections 19b and the center of the disk section is aligned with the centering member 14. Then the projecting sections 19b are press-fitted into the long holes and the wheel is fixed to the wheel receiving member 13.