Abstract: In order to prepare ACE inhibition peptides with high activity, Alcalase 2.4L was selected to hydrolyze bighead carp (Aristichthys nobilis) muscle protein (BCMP) . The single factor experiment was first used to determine the optimal levels of such five parameters as substrate concentration (S) , temperature, pH, enzyme dosage and hydrolysis time based on the ACE inhibitory rate of hydrolyzed BCMP. Then response surface methodology (RSM) was applied to optimize such three parameters as enzyme dosage, temperature and hydrolysis time. The optimal hydrolysis conditions were determined as follows:S6%, enzyme dosage 2.2%, temperature 57℃, pH9.0, hydrolysis time 6.4h. Under the hydrolysis conditions, the theoretical value of ACE inhibitory rate of BCMP hydrolysate was 81.77%. The inhibitory rate in the verification experiment was 81.52%, which conformed to the theoretical value.