Abstract:Andrias davidianus， as an amphibian with high nutritional value， contains abundant collagen in its skin. This study combined the single-factor test method and response surface analysis to determine the optimal extraction process conditions of collagen peptides from the skin of the giant salamander， taking the extraction rate of collagen peptides as the evaluation index. The antioxidant activity of the collagen peptides from the skin of the giant salamander was also determined. The results showed that the optimal extraction process conditions were an enzymatic hydrolysis temperature of 54 ℃， an enzymatic hydrolysis time of 6 h， and an enzyme addition amount of 2 500 U/g. Under these extraction process conditions， the extraction rate of collagen peptides is（0.852 3±0.028 1）%. When the concentration of the collagen peptides from the skin of the giant salamander was 0.5%， the scavenging rate of DPPH free radicals was 55.455%， indicating that the collagen peptides had a good scavenging effect on DPPH free radicals.