The effects of processing parameters including pH, temperature, time, and processing methods including polishing, wiping on coloration quality were investigated by color testing, optical microscope and SEM test . The results show that coloration quality is influenced notably by pH and temperature, processing parameter with pH at 1 . 5 ~ 2 and temperature at 20 ℃ ~ 30 ℃ is the best one, moreover, the color of thin film become black and uniformity of thin film keep steady along with the coloring time increases.