Abstract: Casein is the most important element of milk. Milk-derived bioactive peptides are from casein，they are released by the action of digestive enzymes and directly absorbed in person’s digestive canal，with a variety of biological functions. Casomorphin is one of the most important milk-derived bioactive peptides. This paper reviewed the detection，absorption， and physiological function of casomorphin and introduced domestic and abroad research about casomorphin study in recent years.

Key words: casomorphin; biologically active peptides; high performance liquid chromatography