The compound enzyme composed of trypsin and flavour protease was used to hydrolysate the oyster, chicken and antarctic krill. Taking sensory score, peptide molecular weight distribution and amino acid composition as indexes, the change of them was investigated during ethanol extraction of umami peptide from 3 kinds of hydrolysates. Results showed that the sensory evaluation of supernatant of the 3 enzymatic hydrolysates extracted by 90% ethanol showed strong umami taste and the peptide ratio of the peptide molecular weight distribution < 5 ku from oyster, chicken and Antarctic krill was 93%, 86.82%, 87.86%, respectively . The peptides of 3 enzyme hydrolysates > 10 ku and 5~10 ku were significantly reduced after 90% ethanol extraction. The small molecular peptides of the supernatant of three kinds of hydrolysates extracted by 90% ethanol contained a high proportion of sweet and umami amino acids. The 90% ethanol extraction method can be used for rapid extraction of umami peptide from oysters, chicken and antarctic krill hydrolysates.