Protease is a kind of enzyme that catalyzes protein hydrolysis. It is the general name of a class of enzymes that hydrolyze protein peptide chains. They can be divided into Endopeptidases and terminal peptidases according to the way they degrade peptides. The former can cut the polypeptide chain with large molecular weight from the middle to form prion and peptone with small molecular weight; The latter can be divided into carboxypeptidase and aminopeptidase, which hydrolyze the peptide chain one by one from the free carboxyl end or free amino end of the peptide to produce amino acids.

In feed industry, protease can accelerate protein hydrolysis, improve feed utilization and reduce production cost.