Crude corn peptides were prepared via immobilized enzymatic hydrolysis of corn proteins in nonaqueous media,and its alcohol dehydrogenase and acetaldehyde dehydrogenase activities in vitro were studied.Amino acids composition and relative molecular weight distribution of the peptides were analyzed.Results showed that the highest alcohol dehydrogenase and acetaldehyde dehydrogenase activation ratio were 27.1% and 50.0%,respectively,when the hydrolysis degree reached 22.7%.Corn peptides contained high proportion of alanine,praline and leucine,especially leucine.Molecular weight of enzymatic hydrolysis products were less than 3 548 u,the most were below 1295 Da,taking up about 80%,mainly be 2～10 peptides.