Abstract: In this paper,the ACE- inhibitory activity of three- spot hippocampus peptides were evaluated by studying the preparation technique of three- spot hippocampus enzymatic hydrolysate,screening chromatography separation of ACE- inhibitory peptides and establishing the model.The enzymatic hydrolysate with ACE- inhibitory activity was prepared by alkaline protease,and then separated and purified by gel filtration chromatography.After determination,the lower molecular fraction exerted the highest ACE- inhibitory activity( IC50 was 0.91 mg / m L). The composition of amino acids in it was analyzed,and the test result indicated that the content of hydrophobic amino acids was 50.48%. In addition,it was suggested that the ACE- inhibitory peptides acted as ‘prodrug- type 'inhibitor after establishing the model of artificial gastrointestinal digestion. ACE- inhibitory activity was increased significantly under condition of digestive enzyme digestion.