Abstract: In order to study effects of different hypobaric conditions (43.6, 73.0, 101.3kPa) on antioxidant capacity of tomato, the experiment mainly determined that the contents of vitamin C , lycopene, glutathione and the activity changes of superoxide dismutase (SOD) , peroxidase (POD) , catalase (CAT) . The result showed that hypobaric storage significantly delayed the vitamin C peak of tomato fruit (p<0.05) and the peaks of lycopene and glutathione to some extent were delayed, the lower the pressure, the later of the peak appears. SOD and CAT activities in tomato declined during the storage period after-ripening , hypobaric conditions significantly inhibited the decline of SOD activity (p<0.05) . The activity of POD firstly decreased and then increased during storage, hypobaric conditions could effectively maintain higher activities of antioxidant enzyme. In summary, the tomato storage quality and antioxidant activity in hypobaric conditions were better than in atmospheric pressure, and at a certain rang, the lower pressure, the better effect of the hypobaric storage.