Abstract: Based on the analysis of amino acid composition and molecular weight distribution of oyster peptides and salmon skin collagen peptides, the antiallergic activity and sensitization of two kinds of food-origin oligopeptides were evaluated. The results showed that the oyster peptides and salmon skin collagen peptides were rich in essential amino acids. The peptide content for molecular weight less than 1 000 u was more than 88.5%, mainly in the range of 140-500 u. The main components are dipeptide and tripeptide which are easy to be absorbed. The antiallergic study compared oyster peptides, salmon skin collagen peptides, wheat peptides and corn peptides.It was found that four kinds of oligopeptides can inhibit the activity of hyaluronidase, and IC50 values were 51.47, 79.37, 89.57 and 107.01 mg/mL, respectively. The antiallergic effect of oyster peptides was the strongest, followed by collagen peptides, and corn peptides. The antiallergic activity of oyster oligopeptide and salmon skin collagen oligopeptide further analysis showed anti-allergic activity was negatively correlated with molecular weight of oligopeptide and had some positive correlation with hydrophobic amino acids. The ELISA results showed that sensitization of oyster peptides and salmon skin collagen peptides were significantly decreased compared with the corresponding proteins. The sensitization of oligopeptides with more hydrophobic amino acids was less than those with more hydrophilic amino acids. This study verified antiallergic property and low sensitizing effects. It provided some theoretical support for the development of oyster peptides and salmon skin collagen peptides in food and medicine.