Alcalase2.4L were applied to hydrolyze the Mytilus coruscus protein.Based on the results of single-factor tests,reducing power A700 was chosen as the response values.Using Response Surface Methodology(RSM),the optimum enzyme hydrolysis conditions of Alcalase2.4L to achieve the maximum antioxidant ability were as follows:substrate concentration([S]) 3.20%,[E]/[S]2.12%,enzymolysis temperature 55.54℃,and enzymolysis time 2 hours.Under such conditions,reducibility of the hydrolysate reached 0.587,which also had strong scavenging activity of DPPH radical and superoxide anion radical.