Abstract: On the basis of experiment data on farm for aerobic rice, calibration and evaluation of ORYZA2000 model were done for its simulation of aerobic rice growth. Results of graph and regression analysis showed that the values of aerobic biomass, yield and nitrogen uptake simulated by ORYZA2000 were significantly linear with the observed values, which showed a better simulation effect. However the simulation of soil water potential was not good enough, and more research was needed. According to the results of calibration and evaluation, and combined with fertilizer effect function, the authors explored the optimum economic application amount of N fertilizer under different irrigations and density management for aerobic rice; and derived the optimum application amount of N fertilizer for aerobic rice in the experiment area. The result of the paper enriches the theory and practice of crop simulation and water-saving agriculture, and would be a reference for the development of aerobic rice and its management.