Abstract: To explore a new way for cylindrical precision machining,electrolytic in-process dressing( ELID) precision mirror grinding technology was used for precision and ultra-precision machining of cylindrical. Given ELID precision mirror grinding technology has effectively solved the problem of basal plane precision machining and efficient processing of many typical difficult materials. Through the conversion process of equipment tools,optimization of process parameters,when the duty ratio of twothirds,electrode gap was 0. 3 mm,the wheel speed was 20 m / s,grinding depth was 10 μm,voltage was10 V,and the electricity in 1 A,cylindrical grinding state was the best,and the machined surface roughness Ra can attain 0. 025 μm. So the cylindricol grinding state is best and surface quality of the workpiece is optimal.