In this study, the abrasive testing machine which was similar to the roller mills was used. It used orthogonal test design and cast iron as the wear material. The main factor effected wear results such as abrasive particle size, rotation speed and rolling gap between the metal materials surface of two rollers were considered in order to find out the best value of each factor and optimize the condition of wheat grinding. Furthermore the wear properties of grain powder on cast iron and wear mechanisms were discussed. The results showed that powder size is the most important factor of the wear properties, the gap is the secondary factor and rotation speed is third. The wear loss is minimal while size is 0.2mm, gap is 0.5mm and rotation speed is 181± 2r/min.