The effect of HCl concentration on the oxide layer removal behaviors were investigated for hot-rolled plate of SUS430 stainless steel which was treated by the pickling technology. The oxide layer of SUS430 stainless steel could be removed by the pickling technology. The oxide layer is with the thickness from 5μm to 15μm, and composed of Fe2O3 and Cr2O3. The outer of oxide layer is iron-rich oxide, and inner that have loose structure is chromium-rich oxide. With the increasing HCl concentration, the weight loss of pickling stainless steel quickly increased, and the weight loss is in linear relationship with pickling time.