Abstract: Pig scapula protein was hydrolyzed with protease to prepare antihypertensive peptides. The singlefactor method was used to analyze the effect of the kind of enzyme, time, substrate concentration, enzyme/substrate ratio, hydrolysis pH and temperature on degree of hydrolysis and Angiotensin-converting enzyme (ACE) inhibitory activity of pig scapula protein hydrolysate. Operating parameters such as temperature, hydrolysis time and enzyme/substrate ratio were optimized using response surface analysis based on ACE inhibitory rate. The optimal hydrolysis conditions of pig scapula peptide were enzyme / substrate ratio of6900U/g, hydrolysis temperature of 53℃, hydrolysis time of 4.5h. The theoretical value of ACE inhibitory activity was 66.93%, which was close to the actual value of 65.31%.