This paper describes the plane finishing characteristics of a flat non-ferromagnetic substance (SUS304 stainless steel) by magnetic abrasive finishing process, that is the effects of the various working factors on the stock removal and the surface roughness are clarified by experiments respectively, such as magnetic flux density, circumferential speed of magnetic pole, working clearance, feed rate of workpiece, diameter of magnetic abrasives and thickness of workpiece. On the basis of these experiments, the finishing mechanism is discussed in detail and the characters of this finishing proess are represented summarily. In addition, it is found experimentally that flat ceramics and a silicon wafer are also finished precisely by this process.