PURPOSE: To heighten grinding efficiency and obtain desirable cutting quality by using spherical glass beads as polishing material.

CONSTITUTION: On a base 3 formed of a plastic film, unwoven cloth, foil, a glass plate, or the like, desirably a polyethylene terephthalate film (PE) of about 25-50μm, spherical glass beads 1 are disposed in such a way as to be substantially a single layer using binder resin 2 as adhesive. This results in considerably reducing the probability of scratches or flaws, different in quality (deeper and/or larger) from normal polished streaks, generated by a single grain to the polished surface roughness of polished material determined by the average grain diameter of polishing material grain, so that highly accurate polishing is attained.