The nitrite scavenging activity and N-nitrosodimethylamine(NDMA)interdiction activity of three kinds of red bean peptide was studied in two kinds of simulated gastric fluid.The result showed that with the increase in concentration,the rate of nitrite scavenging and nitrosamine interdiction was increased markedly;there were some different effects on the different of red bean polypeptide,reaction time and simulated gastric fluid.Red bean polypeptide prepared by papain and reacted in the simulated gastric fluid B had the best effectiveness.When the concentration was 1% and the reaction time was 1 h,the rate of nitrite scavenging and nitrosamine interdiction was reached up to 100% and 81.87%,respectively.