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In response to the problem of excessive nitrogen application and low nitrogen use efficiency in summer maize farmland in Guanzhong, Shaanxi, a two-year field trial was set up in Yangling, Shaanxi in 2018 and 2019. Five levels of nitrogen application (conventional nitrogen application N1 (300kg/hm2), 100% slow-release nitrogen fertilizer N2 (300kg/hm2), 65% slow-release nitrogen fertilizer N3 (195kg/hm2), 30% slow-release nitrogen fertilizer N4 (90kg/hm2) and no nitrogen (N0) were set, in which phosphate and potassium fertilizers were applied according to uniform standards, with no fertilizer CK as the control, the effects of different slow-release nitrogen fertilizer application rates on the dry matter accumulation, nitrogen accumulation uptake, soil nitrate nitrogen distribution and accumulation, yield and nitrogen utilization efficiency of summer maize were studied. Explanation of results: the application of nitrogen fertilizer can significantly increase the dry matter accumulation, nitrogen uptake and yield of summer maize. Compared with the local conventional nitrogen application (N1 treatment), the above-ground dry matter accumulation and nitrogen accumulation, nitrogen absorption efficiency, nitrogen partial productivity, yield and other indicators of N2 and N3 treatments were all increased significantly. Two-year trial, there was no significant difference between N2 treatment and N3 treatment in dry matter accumulation, cumulative nitrogen uptake, and yield. However, the partial productivity of nitrogen fertilizer of N3 treatment was increased by 54.61% and 56.25% compared with that of N2, and the agronomic utilization rate of nitrogen was increased by 35.24% and 61.48%, the nitrogen transfer rate of vegetative organs was increased by 17.34% and 18.10%, respectively. Reduced application of slow-release nitrogen fertilizer can significantly reduce the residual nitrate nitrogen in the 0~200cm soil layer, and increase the proportion of nitrate nitrogen in the 0~40cm soil layer. The highest proportion of nitrate nitrogen in the 0~40cm soil layer was N3 treatment compared with other nitrogen application treatments, and it was increased by 6.82%~118.60%. Under the condition that both high yield and high nitrogen use efficiency and low nitrogen loss can be satisfied, the application rate of pure nitrogen of slow-release nitrogen fertilizer of 195kg/hm2 was the best fertilization method in this area.