The results obtained from filed experiment showed that coordination of water and fertilizer could increase maize yield and economic benefits in the region of north of Huaihe rive.Irrigation increased maize yield and profits by 11% and 11.7%,using different dosage nitrogen fertilizer increased maize yield and profits at range of 77.2?.5% and 82.8?.1%.At the same time,coordination of water and fertilizer could increase water and fertilizer utilization efficiency.Water-use efficiency were increased by 70% in treatments of using nitrogen fertilizer,and 5.8% in treatment of irrigation;the recovery rate of N fertilizer was increased by 7.9% in treatment of irrigation.The N fertilizer effective equation at different water conditions have been obtained by mathematic simulation.