To provide a device for grinding and polishing the surface of an object to be treated having a complicated form or the like by dispensing polishing abrasive grains, which are carried by rotating a conveyer belt while accelerating the abrasive grains.

In this grinding and polishing device, the conveyer belt having a conveying part for abrasive grains is wound between a motive force transmission pulley connected to a motive force source and the other auxiliary pulley, an abrasive grain holding mechanism is provided for guiding the abrasive grains in a rotating direction to surround both the sides and the surface of the conveyer belt, a fixed or variable abrasive grain dispensing port is disposed in the extending direction of the horizontal plane of the conveyer belt hung over the motive force transmission pulley, and a hopper having an abrasive grain feeding port 5 is disposed at a position lower than the abrasive grain dispensing port. When the abrasive grains are conveyed upward, continuously supplied from the hopper onto the conveyer belt close to the upper part of the auxiliary pulley by the rotational force of the conveyer belt while the conveyer belt rotates, the abrasive grains are dispensed with acceleration from the abrasive grain dispensing port so that the surface of the object to be treated is ground and polished.