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To systematically analyze the effects of nitrogen application on cotton yield and water use efficiency under different climatic conditions, soil foundation conditions, and farmland management measures, totally 103 published Chinese and English literatures from China were collected, among which 37 papers were selected, and a total of 301 sets of yield and 127 sets of water use efficiency data were obtained. Based on the Meta-analysis method, the impact of nitrogen application on cotton yield and water use efficiency under different production conditions was quantitatively analyzed, and partial correlation analysis was used to identify the main influencing factors of cotton yield and water use efficiency under nitrogen application conditions. The results showed that with no nitrogen application as the control, nitrogen application can significantly improve the yield and water use efficiency of cotton. The effect of nitrogen application on yield and water use efficiency was most significant in areas with an average annual precipitation of 200~500mm, with effects of 34.02% and 54.15%, respectively. The effect of nitrogen application on yield and water use efficiency was increased with the increase of sunshine hours. When the soil pH value was 6~8, nitrogen application had the most significant effect on improving cotton yield and water use efficiency, with the effective amounts being 28.52% and 24.59%, respectively. The effect of nitrogen application on yield and water use efficiency in different soil textures was the highest in sandy soil, with 46.71% and 26.29%, respectively. As the frequency of fertilization was increased, the effect of nitrogen application on cotton yield and water use efficiency was gradually increased. The effect of nitrogen application on yield was increased with the increase of irrigation amount, and the effect on water use efficiency showed a trend of first increase and then decrease with the increase of irrigation amount. When the nitrogen application rate was 300~450kg/hm2, nitrogen application had the most significant effect on improving yield and water use efficiency. When the planting density was 1.5×105~2.5×105 plants/hm2, nitrogen application had the most significant promoting effect on yield and water use efficiency, with effective amounts of 38.48% and 16.46%, respectively. The nitrogen application rate and soil pH value were the main influencing factors on cotton yield under nitrogen application conditions. The nitrogen application rate and irrigation amount were the main influencing factors of cotton water use efficiency under nitrogen application conditions. The research results can provide reference for achieving high yield and efficiency in cotton cultivation under different production conditions.