Abstract: The application of methanesulfonic acid pickling-masking-chrome tanning system in the sofa leather processing was investigated and compared with the conventional technology. The results showed that methanesulfonic acid pickling-masking-chrome tanning system can effectively promote the chromium penetration, and increase the reaction rate and fastness between chromium and hide collagen by controlling the pickling pH 3.0 and the dosage of chromium during chrome tanning. Therefore, the chromium absorbability increased from 74.5% in the conventional process to around 91.9%, and the residual Cr concentration in effluent of chrome tanning decreased from 1076.7 mg/L to 372.3 mg/L. As a result, this system significantly increased the chromium content in each layer of wet blue leather and reduced the chromium release in wet processing after tanning, thus achieving high absorption and high fixation of chromium.