Added a magnetic field whose direction is parallel to the electrical field’s directions, the charged particles between two electrodes can move in spirals in magnetic-electrochemical compound polishing, and then the condition of chemical reaction is improved. The efficiency and quality of polishing can be promoted consequently. If the direction of magnetic field is changed alternative, the effect of polishing can be improved more clearly. In the paper, a new magnetic-electrochemical compound polishing tool is developed. The tool can be fixed on spindle of CNC easily. The tool is flexible, so it can make the polishing head and workpiece touch evenly each other. Because the head of magnetic-electrochemical compound polishing tool is a series, the head can be replaced conveniently according to different surface. Particularly, the tool can set a magnetic field whose direction is parallel to the electrical field’s direction. The tool can change strength of the magnetic field easily. At last, the tool is tested and its function is perfect.