Abstract: The field experiment was conducted with peanut‘shan G'as material, in the experimental station of Agricultural Ecology Institute, Fujian Academy of Agricultural Sciences to study the effects of N application amount on physiological characteristics, yield and quality of dual-purpose peanut.The results showed that different nitrogen fertilizer treatments increased chlorophyll content and photosynthetic rate in peanut leaves, with greater increasing extent at middle-later stage (pod filling stage) than that at the middle stage (pod setting stage) .Nitrogen application enhanced the activities of catlase (CAT) and the contents of soluble protein, but reduced malondialdeyde (MDA) content in peanut leaves, especially treated by N300and N450.Nitrogen application led to the highest yields of peanut and peanut vine, and reached the highest when applying N 300kg·hm-2 level.In addition, the application of nitrogen fertilizer also increased the contents of lysine and methionine, which were inadequate in the protein fractions of peanut kernel, to improve nutritional quality of peanut.