[Objective] The effect of different combined application rates of organic fertilizer and chemical fertilizer on nitrogen supply capacity and greenhouse gas emission of tobacco-growing soil is explored, which provides scientific guide for improvement of yield and quality of tobacco leaves, adjustment and perfection of fertilization method. [Method] Rapeseed cake (RC), pig manure (PM), carbon-based organic fertilizer (BOF) and peanut straw (PS) were selected as the test organic materials, and the nitrogen substitution ratio of chemical fertilizers was set at two levels, 30% and 50% respectively.Through the pot experiment, the differences in agronomic characteristics, biomass, soil mineral nitrogen content, soil organic carbon content, greenhouse gas emissions of flue-cured tobacco between treatments were compared. [Result] Compared with chemical fertilizer treatment (CK), except for BOF treatment, other combined organic fertilizer treatments all reduced the mineral nitrogen content of the soil by 22.9%-57.84% (resettling growth stage), 4.97%-66.04% (prosperous growth period), 25.59%-83.82% (budding period), 33.58%-68.90% (mature period) .Except for peanut straw treatment, other organic fertilizer treatments did not significantly reduce the biomass of flue-cured tobacco roots, stems and leaves.Only the combined application of pig manure and peanut straw treatment significantly increased CO2 emissions by 23.74%-33.40% and 61.75%-87.54% respectively.Only when the proportion of organic materials was 50%, the N2O emission was significantly increased, and the increase was 7.73-21.89 times.The combined application of organic materials increased the total nitrogen content of the soil by 1.56%-20.68%, and also significantly increased the total soil carbon content by 2.77%-16.63%.Rapeseed cake treatment significantly reduced soil C/N ratio, while peanut straw treatment significantly increased soil C/N ratio, but pig manure and carbon-based organic fertilizer treatment had no significant effect on soil C/N ratio. [Conclusion] Comprehensive comparison showed that carbon-based organic fertilizer was suitable for tobacco planting.From the aspects of nitrogen supply capacity of tobacco soil, biomass of tobacco plant and N2O emission, the proportion of organic materials should be 30%, and shouldnot be higher than 50%.In order to maintain the carbon and nitrogen balance of tobacco planting soil, rapeseed cake with low C/N ratio and peanut straw with high C/N ratio should not be applied separately and continuously. [ABSTRACT FROM AUTHOR]