To provide a backing plate which develops a sufficient vibration control effect without affecting a productivity and a production cost.

The backing plate is integrally formed by overlapping, in a thickness direction, a plate material 21 formed of a cast iron powder sintered body and a steel plate 22. Vibration noise incident on the backing plate 11 is scattered and attenuated by utilizing graphite distributed in the sintered body and, at the same time, the transmission of the vibration noise is attenuated in the boundary of a connection part between the plate material 21 and the steel plate 22. By adjusting the material and shape of the steel plate 22, a mechanical strength and toughness required for the backing plate 11 are assured. By integrating the plate material 21 with the steel plate 22 by a diffusion connection, special connection steps formed mainly of welding and adhesion are eliminated to suppress the lowering of a productivity and an increase in production cost due to an increase in the number of layers of the backing plate 11.