Abstract: Abrasive grains are produced by gluing an abrasive powder to an elastic porous carrier. A number of abrasive grains are mixed with an abrasive liquid, and are then sprayed to the surface of a work at an oblique angle thereto to impact it while allowing the abrasive grains to slide on the surface of a work to finish the surface of the work. Over the distance of travel over which the abrasive grains slide, the surface of the work are ground. The elasticity of the carrier allows the abrasive grains to deform matching the contour of the work. By spraying a number of abrasive grains on the work, grinding action is performed in consideration of the contour even if the work is a complicatedly contoured surface such as a dental prosthesis while a polishing effect is obtained at the same time.