Selenium-chelating porn oligopeptide were prepared by using pea oligopeptide and sodium selenite. The properties of moisture， acid soluble protein， total nitrogen and molecular weight distribution were analyzed. Taking scavenging effects on DPPH， OH free radicals and reducing power as indicators， the antioxidant function of raw materials and chelates were evaluated and compared in vitro. The results showed that the yield was 27.87%， the moisture content of the product was （14.17 ± 1.12）%， the acid soluble protein accounted for 97.28% of the crude protein， and the molecular weight below 1 000 u was 93.45%. For raw materials， sodium selenite only had strong OH radicals scavenging ability； for pea oligopeptides， the median inhibitory concentrations （IC50 values） of DPPH radical and OH radical scavenging activities were （3.39 ± 0.02） mg/mL and（23.55 ± 0.07） mg/mL， respectively， and the pea oligopeptides showed some reducing power. While for selenium-chelating pea oligopeptides， IC50 of DPPH radical and OH radical scavenging activities were （1.77 ± 0.01） mg/mL and （3.28 ± 0.04） mg/mL， and showed certain reducing power， better than pea oligopeptides。