Abstract: Silicon nitride ceramic ball is the key element of bearings in heavy equipment, and the ultra-precision grinding and polishing quality of the balls is an important factor affecting the bearing performance and life. From the angle of the processing method, the research progress of ceramic ball grinding and polishing technology is summarized. The method of ultra-precision compound polishing for different silicon nitride ceramic balls is compared and analyzed. A new method of grinding and polishing, that is, the method of cluster magnetorheological polishing, is put forward. Preliminary tests show that by the method of 3 hours of polishing, silicon nitride ceramic ball surface roughness Ra can reach 5 nm, and sphericity is 0.11 to 0.22 μm.