Abstract: The invention is about methods for preparing functional polypeptide by multi-mode ultrasound enhancement on enzymolysis, and it relates to the field of functional peptide production technologies. The objective of the invention is to improve the degree of hydrolysis of protein, increase the anti-hypertensive activity of protein hydrolysate, shorten the enzymolysis time and reduce the energy consumption. To achieve this, some methods are developed, such as the method for preparing the anti-hypertensive peptide from wheat gluten by sequential ultrasound enhanced enzymatic hydrolysis, preparation of anti-hypertensive peptide from corn gluten by ultrasonic reverberation field, and the technology for preparing functional polypeptide by countercurrent mode dual frequency ultrasound pretreatment of prion protein. The invention of solid-liquid scanning ultrasonic pretreatment of corn gluten meal suspension leads to an improved efficiency of enzymatic hydrolysis.