Ulltra fine grinding machine of 27 rollers is for super-fine grinding materials with hardness less than 6 in Moh's scale and humidity less than 6 percent such as kaolin, limestone, basalt, calcite, marble, talcum, barite, gypsum, dolomite, bentonite mud, mica, pyrophyllite, sepiolite, carbon black, diatomite, graphite, alunite, fluorite, potassium feldspar, phosphorite, pigment, up to 200 kinds.