Abstract: It has been verified that the chrome sludge gathered from hydrolyzed chrome shavings contains high constitution of protein. When the chrome sludge was directly dissolved by sulphuric acid, the wet blues tanned by that revealed a low shrinking temperature. This is the reason why the further recycling was being restricted. Based on this, enzymatic hydrolysis was applied to regulate the protein content of the chrome sludge in this paper. The results indicated that the protein content was reduced more than 75% when the enzyme dosage was 1%. When the dosage of the recycled chrome tanning agent prepared from the chrome sludge was equal to a commercial one, the wet blues has a light color. Furthermore, the absorption of Cr2O3 was more than 78%. Moreover, the physical-mechanical properties of the leather can reach the industry standards, indicating that the recycled chrome tanning agent prepared by the chrome sludge can save part of the commercial agent consumption.