【Objective】 The effects of different fertilizer application and seeding density on the agronomic characters and yield of broom sorghum were studied in order to provide theoretical basis for the determination of reasonable fertilizer application and seeding density in the large-scale production of broom sorghum. 【Method】 In 2017-2018,Chitiao 100 was used as the experimental material,and the two-factor split zone design was used.A （application rate）was the main treatment factor,and three levels were set,namely:A₁ was 150 kg/ha diammonium phosphate and 75kg/ha potassium sulfate,and 300 kg/ha urea was applied at the jointing stage.A₂ is slow-release long-acting compound fertilizer 450 kg/ha;A₃ was 300 kg/ha compound fertilizer and 300 kg/ha urea at jointing stage.B （seeding density） factor was secondary treatment with 4 levels.B₁ 67 500 plants/ha,B₂ 90 000 plants/ha,B₃ 112 500 plants/ha,B₄ 135 000 plants/ha,repeat 3 times. 【Conclusion】 The yield of tassels with different fertilizer rates and planting densities was significantly different.Fertilizer density interaction was not significant,and A₁B₃,the combination of the best treatment A and the best treatment B,was the optimal treatment combination,and the yield of broom sorghum reached 3 972.87 kg/ha.