The Nan Feng Mandarin is a special native product of Jiangxi province in China, It's characterized by thin rind with few pits, much juice without dregs, good taste of sweet, fragrance and sour in goden color. However it can not be stored for a long time because of its thin rind and much juice. This paper has studied the effect of the radiation on the preservation of the Nan Feng Mandarin. The results showed that when the mandarin was stored at a room temperature for 100-120 days and irradiated at a low dose of ,60,Co ray, the rate of good one was up to the 80%, and 10-15% highter than that of the controlled Mandarin. But any distinct changes of main chemical compositions of the irradiated Mandarin haven't been found by examining. In addition, this paper has also preliminarily shed light on the mechanism of the radiation on the presevation of the Nan Feng Mandarin.