Abstract: Objective In order to research the influence of chemical methods on the flower thinning effect and quality of Prunus salicina × armeniaca to screen the suitable chemical agent and concentration and to propose a simple method of flower thinning and control reasonable crop load.Method Three cultivars of Prunus salicina × armeniaca were taken as materials,different concentrations of three kinds of chemical flower thinning agents were sprayed at full-bloom stage and then the fruit setting rate and quality were determined.ResultThe results showed that when Fengweihuanghou was sprayed one time 20 mg/L NAA and 0.3°Be lime-sulfur at full-bloom stage,Konglongdan was sprayed 30 mg/L NAA and 0.4° Be lime-sulfur and Weidi was sprayed 30 mg/L NAA and 0.4°Be lime-sulfur,the fruit setting rate of these treatments was lower than that of the CK,and the fruit shape index,soluble solid content and sugar content and acid content were significantly improved.Conclusion Spraying one time 20 ～30 mg/L NAA and 0.3 ～0.4° Be lime-sulfur has better effects of flower thinning at one day or two days of full-bloom stage and can improve the quality of fruits.