In order to determine the effects of plastic box modified atmosphere storage on the antioxidant system of fresh-cut Fuji apple,the condition of 5% O2 +5% CO2 and 5% O2 + 10% CO2 atmosphere at 5℃ were established in this experiment.Meanwhile,the activity of enzymatic defense system,the concentration of non-enzyme antioxidants as well as respiration rate,rot rate and browning degree were measured every 3 d.The results indicated that two kinds of plastic box modified atmosphere with high CO2 were all able to start the enzymatic defense system.Therefore,not only the peroxidase(POD),catalase(CAT) and superoxide dismutase(SOD) activities were increased,but the consumption of antioxidant in non-enzymatic defense system were also accelerate.The total phenolics,Vc and reduced glutathione(GSH) content were decreased.Moreover,5 % O2 + 5 % CO2 and 5 % O2 +10 % CO2 effectively slowed down the respiration rate,inhibited the occurrence of decay and reduced the degree of browning.Apples stored with 5 % O2+5 % CO2 was better in controlling the browning,while 5 % O2 +10 % CO2 was better in inhibition decay.