Abstract: The effects of pickling-Chrome tanning methods including conventional pickling, methanesulfonic acid pickling and salt-free aromatic sulfonic acid pickling were compared with each other, and the changes of chromium (Cr) and chloride concentrations in the spent tanning liquors with recycling times and the influences of them on chrome tanning effectiveness were investigated. The results indicated that, compared with conventional technology, the Cr concentrations in the spent chrome tanning liquors were reduced to 153.5 mg/L below from 1142 mg/L by both methanesulfonic acid and aromatic sulfonic acid pickling-chrome tanning methods. Recycling the spent chrome tanning liquors to the operations of pickling and tanning by 10 times, the contents of chromium and chloride in the spent liquors of conventional technology fluctuated greatly, resulting the Cr contents and shrinkage temperatures of chrome tanned leather changed randomly. The concentrations of chromium in the liquors from methanesulfonic acid and aromatic sulfonic acid pickling-chrome tanning methods kept below 400 mg/L, which helps to improve the technological stability of direct recycling of chrome tanning liquors.