Abstract: 【Objective】 The purpose of this project is to study the dynamics and rules of source sink characteristics and yield formation of spring wheat in drip irrigation under nitrogen-fixing cultivation and to propose a stable and high-yielding population structure control index in order to seek the best nitrogen application rate.【Method】Five nitrogen fertilizers gradients were set up in this experiment: Xinchun 31 (high pole) and Xinchun 6 (short pole), 300 kg/hm² (N1) and 275 kg/hm², 250 kg/hm² (N3), 225 kg/hm² (N4) and no nitrogen fertilizer (N5).【Result】The results showed that the quality of 275 kg/hm² (N2) and 250 kg/hm² (N3) populations was the best under the treatments of N application and Xinchun 6, The rate of LAI at the booting stage reached 7.7 and 6.8, respectively, and the ratio of grain number to leaf and grain weight to leaf also reached 4,215.8 seeds/m², 199 g/m² and 4,233.2 seeds/m², 203.9 g/m². The contribution rate of post-anthesis dry matter accumulation to yield also reached 75.04% and 75.52% respectively. The highest yield of N2 was obtained in New Year 31, which was 3.5%-37.7% higher than that of other treatments. The highest yield of N3 was obtained in Xinchun 6, which increased by 2.5%-33.5% compared with other treatments. Through the path analysis of yield components, the combination of 1,000-grain weight and grain number per spike had the greatest effect on the yield of Xinchun 31 and Xinchun 6, respectively, with coefficients of 0.755,9 and 0.525,2. After the nitrogen application rate and the yield were fitted, it was found that the yield reached the highest when the nitrogen application rates reached 286 and 258 kg/hm².【Conclusion】In this experiment, nitrogen fertilizer was reduced by 300 kg/hm² (N1) in high-yield nitrogen crops in wheat fields in Xinjiang. The results showed that the amount of nitrogen fertilizer applied in the treatment of Xinchun 31 was 275 kg/hm²(N2). Xinchun 6 was 250 kg/hm²(N3) significantly improved the wheat population structure. Therefore, it can be shown that appropriate reduction of nitrogen can optimize population structure to achieve high yield, but for different types of varieties, nitrogen application rates suitable for local cultivation conditions should be selected.