Abstract: In order to delay senescence and prolong the shelf-life of fresh-cut Agaricus bisporus,the effects of filling nitrogen in different vacuum(0,-20,-40,-60,-80,-98 k Pa) combined with heat treatment on superoxide anion production,hydrogen peroxide(H_2O_2) content,enzyme activities of superoxide dismutase(SOD),catalase(CAT) and ascorbate peroxidase(APX),and ascorbic acid(As A) content of fresh-cut Agaricus bisporus under cold storage were evaluated. Results showed that lower vacuum(-20~-60 k Pa),especially-40 k Pa filling nitrogen in vacuum with heat treatment significantly(p<0.05) decreased superoxide anion production and H_2O_2 accumulation, and increased activities of SOD and CAT of fresh- cut Agaricus bisporus. Higher vacuum(-98 k Pa) treatment enhanced As A content remarkably. Filling nitrogen in vacuum combined with heat treatment obviously inhibited APX activity of fresh-cut Agaricus bisporus.