Based on the preparation of sesame peptides, the effect of Maillard reaction on antioxidant activity of sesame polypeptides was studied. The results showed that the suitable ratio of peptide to sugar was 1∶2 for Maillard reaction of sesame polypeptide. The Maillard reaction could significantly improve the antioxidant activity of sesame polypeptide, and the reducing power, ABTS⁺ radical scavenging rate, DPPH radical scavenging rate and hydroxyl radical scavenging rate were increased by 121.4%, 304.5%, 81.2% and 103.2%, respectively. The contents of lysine methionine and tyrosine were reduced, but the contents of alanine and valine were increased, moreover, aspartic acid, glutamic acid, cysteine and glycine were produced by Maillard reaction of sesame peptides. Browning degree and graft degree increased with the prolongation of Maillard reaction time. When the reaction was carried out for 4 hours, the browning degree and graft degree were 1.42%and 26.4% respectively. The Maillard reaction products have absorption peaks at 210 nm and 260 nm, and with the increase of reaction time, the absorption peak intensity was increased gradually. It was related to the change of peptide bond and the increase of melanoidin content in the Maillard reaction products. Therefore, the Maillard reaction had a certain effect on the antioxidant activity of sesame peptides.