A vernier type coix seed huller, solve the gap existing sheller to barley precise adjustment, low production efficiency, high crushing rate; the invention has as an outer barrel cover, the outer barrel is arranged in the inner sleeve, the inner sleeve of a bearing seat, the bearing seat is provided with a rotating the rotation shaft, the shaft is provided with a wheel in the upper part of the outer barrel, an upper cover is arranged at the lower part of the upper cover, a fixed wheel and the wheel to match, which is on the cover is composed of an inner ring and an outer ring between the inner and outer rings threaded connection, to adjust the clearance between the fixed wheel and wheel by screw; there are several scale positioning holes in the outer ring, a pointer on the inner ring, between the fixed wheel and the wheel trimmer; has the advantages of high precision adjustment, convenient, fast, so that the invention can adapt and processing of different varieties, different degree of satiation Riesling M, and ensure that the coix seed and coix seed skin is not broken, and increase production efficiency.