The radiation effects on respiration and ethylene production in apple and its radiation preservation were reported in this paper. It shows that, when irradiation was applied immediately after harvest, the respiratory rate and ethylene production increases with the increasing of irradiation dose. When irradiation was applied after 7-10 days of storage, the respiratory rate still rises with the dose, while there is a decrease in ethylene production with the increasing of dose. If the irradiation dose is less than 800 Gy the rise of respiratory rate of irradiated apple caused by the irradiation came back to the level of the control within 5 days, but ethylene production of irradiated apple keeps a lower level. According to the above results, dose of 300-500 Gy may be recommended for radiation preseration of apple.,Ascorbic acid is unstable and is sensitive to radiation, but the radiation effects on ascorbic acid in apple is very small, because the saccharides and some organic acid in apple, especially malic acid are able to protect ascorbic acid in apple from radiation damage. From measuring the saccharides and acids in apple, it is obvious that there is no significant difference between irradiated and unirradiated apple.,Long-life free radical in apple was not detected after irradiation. Scald of apple reduced from 60% to less than 15% after cold storage for 8 monthes. The taste results indicated, tasting them without knowing which is irradiated or not, that the irradiated apple is superior to controlled sample.