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[Objective] The present paper aimed to provide theoretical basis for rational application of nitrogen fertilizer to wheat, effects of reduced application rates of nitrogen on yield and quality of wheat were analyzed in Yunnan province. [Method] Using a two-factor randomized block design, the newly bred dryland wheat varieties Yunmai 76 and Yunmai 77 were used as materials to set up a nitrogen-use efficiency experiment including 5 N application rates, namely, 300 kg/hm²(N1),240 kg/hm²(N2), 180 kg/hm²(N3) and 120 kg/hm²(N4) and no nitrogen fertilizer(N5), respectively. The related indexes of grain yield, yield components and quality under different rates were determined. The correlation between grain yield and spike number, grain number per spike and 1000-grain weight was analyzed. [Result] Under different nitrogen application rates, the yield of Yunmai 76 and Yunmai 77 decreased with the decrease of nitrogen application rates. When the nitrogen application rate decreased from 300 kg/hm² to 240 kg/hm², the yield decreased by 1.38% and 0.30%, respectively; When the nitrogen application rate decreased to 180 kg/hm²or below 180 kg/hm², the yield was significantly decreased. In terms of yield components, the number of panicles per unit area significantly decreased with the decrease of nitrogen application rate; However, the effect of nitrogen application rate on 1000-grain weight and grain number per spike was not significant. The results of correlation analysis between yield and components showed that there was a extremely significant positive correlation between yield and panicle number(R=0.92）. There was no significant correlation with grain number per spike, but a significant negative correlation with 1000-grain weight. Under the rateof N180 kg/hm² and no nitrogen application, the yield of Yunmai 77 was 10.67% and 28.87% higher than that of Yunmai 76, respectively, and the yield decrease of Yunmai 77 was much lower than that of Yunmai 76 under the same N treatment. In terms of quality, protein content and wet gluten content decreased with the decrease of nitrogen application rates, and the differences were significant; The responses of sedimentation value, stability time and formation time to nitrogen application varied with different varieties. The sedimentation value of Yunmai 76 decreased at first and then increased with the decrease of nitrogen application rate, but the nitrogen reduction rate had no significant effect on the sedimentation value of Yunmai 77. [Conclusion] Yunmai 77 is a wheat variety with tolerant low nitrogen. Considering the yield and quality comprehensively, under the experimental conditions, when the conventional nitrogen application rate in this area is 300 kg/hm², the synergistic improvement of wheat yield and quality can be realized [ABSTRACT FROM AUTHOR]