In this paper, a thin SS304 stainless steel is chosen as metallic bipolar plate. In order to improve the surface qualities, such as anticorrosion capability, surface roughness, and clearness, the surface of bipolar plate is treated by an electropolishing technology. From the results of corrosion and potentionstatic tests, the corrosion rate and corrosion current of treated plate are much improved. The corrosion rate and corrosion current are reduced to 0.037 mmPY and . The cell performance tests show the peak power of treated cell is lower than original cell. However, for the long term tests, the cell with treated plate has a more stable power output. The results show that the treated plate has a good potential for using in the fuel cell.