Abstract: The preparation process of α-glucosidase inhibitory active peptides from sea mustard was optimized by response surface method in order to obtain a new effective ingredient for regulating postprandial blood glucose. Five proteases were selected to hydrolyze sea mustard protein. The effects of substrate concentration,enzyme-substrate ratio,pH,temperature,and hydrolysis time on inhibition rate and degree of hydrolysis were studied. Based on the results of single-factor experiments,Box-Behnken design principle was used to perform a three-factor and three-level response surface optimization test. Then the molecular weight of the hydrolysate was measured and the kinetic curve of enzyme inhibition was drawn. The optimal hydrolysis conditions were:Alcalase,substrate concentration 7.11%,pH10.14,temperature 47 ℃,enzyme concentration 10000 U/g,and reaction time 1 h.Under these conditions,the inhibition rate was 51.17%. The half-inhibitory concentration of the sea mustard hydrolysate was 46.079 mg/mL,and the inhibition type was typical reversible mixed-type inhibition. In this study,the optimal preparation technology and physicochemical properties of α-glucosidase inhibitory active peptides from sea mustard were obtained,which provided theoretical and experimental basis for the development of novel hypoglycemic active peptides.