This research proposes an effective plane magnetic abrasive finishing (MAF) process which was combined with electrolytic process in order to improve machining efficiency of traditional plane MAF process. The new plane finishing process can make surface of workpiece to be planarized and softened through formed passive films from electrolytic process. Meanwhile, the passive films are removed by magnetic brush-generated mechanical processing force to achieve efficient precision machining. This finishing process is called electrolytic magnetic abrasive finishing (EMAF). In this research, we have developed a novel machining tool of compound magnetic poles and electrodes, which is able to achieve two different processes. The SUS304 stainless steel plane is used as workpiece. In order to select electrolytic finishing time for EMAF process, the investigation of electrolytic process has been carried out before EMAF process. Then, the comparative experiments of EMAF process and MAF process have been conducted in order to investigate the effect of EMAF process. The experimental results show that EMAF process can a little obtain higher quality surface, and machining efficiency is improved by about 50%, which compared with that of traditional plane MAF process. Furthermore, the surface roughness can be reduced to 30.94 nm R a from original roughness of 393.08 nm R a in 40 min by the EMAF process.