To provide a low-priced rotary polishing wheel assembly which can be used for finishing a rubber product, such as a tire casing.

The polishing wheel assembly includes three rotary wheels, a pair of side supporting wheels (24, 24) and a central polishing wheel (22) arranged between the side supporting wheels. The three wheels are made of sheet metal material by punching, and have one, or two or more holes (26) for receiving a polishing tool driving shaft. The central polishing wheel has a diameter larger than those of the side supporting wheels, and provides a polishing peripheral portion, which includes a series of teeth separated in the peripheral direction.