Soil moisture is an important factor restricting agricultural development in arid and semi-arid regions of northwest China. It is of great theoretical and practical significance to explore a scientific and reasonable relationship between nitrogen fertilizer,water and yield for promoting the sustainable development of regional agriculture. At the Changwu Loess Plateau Agro-ecological Experiment Station of the Chinese Academy of Sciences in Changwu County,Shaanxi Province,a nitrogen fertilizer decline test was performed. Based on the traditional nitrogen application of 250 kg/hm² (N6),it was reduced by 20% in order. Set CK,N1,N2,N3,N4,N5,N6 seven processes. The results showed that: (1) The soil water consumption during the growth period of spring corn increases with the increase of nitrogen fertilizer application. The soil water deficit mainly occurs below 80 cm of soil layer,and the degree of water deficiency increases with the increase of nitrogen fertilizer application. (2) Both the yield and water use efficiency of spring corn showed a second parabolic trend with the increase of nitrogen fertilizer use. The traditional nitrogen application rate of spring corn (N6,250 kg/hm²) has been severely excessive,and a reduction of 20% (N5,nitrogen application rate of 200 kg/hm²) can achieve higher yield and water use efficiency. Compared with N6,N5 grain output increased by 9.6% and 5.8%,and water use efficiency increased by 14.5% and 9.1%. Therefore,it is recommended to reduce nitrogen by 20% (N5,200 kg/hm² nitrogen application rate) as the recommended nitrogen application rate.