In order to explore the best scheme of combined application of nitrogen，phosphorus and potassium，and provide reference to scientific fertilization of Jasminum sambac，the representative plot of the local planting area was selected as the test site，and the main double petal varieties planted in Hengzhou with 15 years of original tree age in the test site were used as the test materials.The“ 3414” experimental design was used to carry out the fertilization effect test to study the impact of combined application of nitrogen，phosphorus and potassium on the yield and the flood season of flowers in Hengzhou，to clarify the difference of demand for nitrogen，phosphorus and potassium in flowers yield under environmental conditions of Jasminum sambac planting area in Hengzhou，and provide a theoretical basis for scientific fertilization and increase of flowers yield.The results showed that:(1) For the production of flowers，the available nitrogen content in the soil of the experimental site of Jasminum sambac planting in Hengzhou of Guangxi was excessive，while the available phosphorus and potassium were at a medium low level.(2) In the interaction effect of nitrogen，phosphorus and potassium fertilizer，phosphorus and potassium fertilizer had the highest interaction effect，the interaction effect of nitrogen，phosphorus and potassium fertilizers fertilizer was the second，the interaction effect of nitrogen and potassium fertilizer was the last.(3) The daily yield of flowers increased and decreased synchronously under different fertilization treatments，and the effect of different nitrogen，phosphorus and potassium combined application on the flood season of flowers was not significant.(4) In the stable flowering period of jasmine(June to September)，the flood season of flowers occurred in all months，the average daily output was the highest in July and the most stable in August.(5) The combined application of nitrogen，phosphorus and potassium had a significant effect on the yield of flowers，and the effect on the yield of flowers from large to small was:phosphorus fertilizer>potassium fertilizer>nitrogen fertilizer.(6) In this study，the fitting of the ternary quadratic equation was not successful.In the aspect of the unary quadratic equation，only the effect equation of nitrogen fertilizer was successfully fitted，and the effect equations of phosphorus fertilizer and potassium fertilizer were all failed.In the binary quadratic equation，the three effect equations of nitrogen and phosphorus fertilizer，nitrogen and potassium fertilizer，phosphorus and potassium fertilizer were successfully fitted.After solving the equation successfully fitted，excluding the amount of fertilizer that cannot be reached in actual operation，and comprehensively considering factors such as excess content of soil available nitrogen and reduction of investment cost of planters，the recommended fertilization method and amount are as follows:phosphorus fertilization amount is 393.64 kg/hm²，potassium fertilization amount is 381.59 kg/hm².