Abstract: A simple field electrolytic polishing & corrosion device for metallographic examination was designed for the situation where the mechanical polishing takes a long time, the work intensity is high and the sample preparation effect is not ideal. The general engineering used low alloy steel 20MnNiMo, stainless steel 06Cr19Ni10 and nickel base superalloy 00Cr30Ni60Fe10 were tested. The results show that the device has the advantages of simple operation, less time consumption, high efficiency, etc., the effects of electrolytic polishing and electrolytic corrosion are both good, and the microstructure of the field workpiece can be clearly displayed.