Abstract: In order to investigate the effect of different amount of nitrogen (N) fertilizer on maize, the yield, grains per ear, 1000-grain weight, dry weight, harvest index, the ratio of return on invested, and agronomic N efficiency of corn hybrid ‘Longping 206’ (Zea mays L.) were analyzed. Results showed that, the yield of maize was significant different under different amount of N (0, 75, 150, 225, 300, 375 kg/hm2). The yield of maize increased with the augment of N from 0 kg/hm2to 225 kg/hm2. In details, when the plants was applied with 0 kg/hm2, 75 kg/hm2, 150 kg/hm2 and 225 kg/hm2, the yield were 7354.0, 9462.5, 10847.3, 11352.6 kg/km2, respectively. However, in contrast to 225 kg/hm2 N, there was no significant increase in yield when the plants were applied with 300 kg/hm2 and 375 kg/hm2. So, the relationship between nitrogen and yield were linear plus plateau. And the mathematical simulation equation was: y=23.37x+7475, x<169; y=11426, x>169 (R2=0.97**, n=18). Accordingly, the optimum amount of N in Jianghuai area was 169 kg/hm2, which layed a theoretic foundation for reasonable use of nitrogen for maize production in Jianghuai area.