Abstract: A field experiment was carried out to study the influence of nitrogen fertilization on the grain yield and nutritional quality of maize (Qianxing 2302). Results showed that N application increased grain yield from 9.59% to 23.14% compared with control (without fertilization), and improved proteins, amino acids, starches and fatty acids content in grain. Furthermore, N application did not change the ratio of amylase to amylopetine. In maize grains, the contents of MET, PHE, LYS, ASP, SER, GLU, GLY, HIS and flax acid were rather consistent and mainly controlled by genes instead of fertilization. However, the other nutrient elements, i,e, albumin, globulin, prolomine, glutamine, THR, VAL, ILE, LUE, ALA, TYR, PRO, amylase, amylopetine, oleic acid, sub-oleic acid, palm acid and stearic acid was varied with both genes and nitrogen fertilization. In general, applying about N 150 kg/ha fertilizer was optimal for Qianxing-2302 for the purpose of higher yield with better qualities.