According to modern orchard planting pattern, a new self-propelled electric sprayer with multi-angle variable speed swing nozzle function was developed to accommodate the small space and the poor traffic-ability of conventional orchards which are densely planted with dwarf plants. A 4 factors and 3 levels of test was performed according to the Box-Behnken center-united experimental design principles. To find influence factors of droplets deposition distribution, the parameters were analyzed by using response surface methodology including spraying flow rate,spraying distance, angular swing speed and sprayer forward velocity. Subsequently, a mathematical model was established by using Design-Expert software,then the effects of various parameters and their interactions were discussed. The results showed that the effects order of the four parameters on distribution of droplets deposition ranked from large to small as: sprinkler swing speed,spraying distance,spraying flow rate, and sprayer forward velocity. The optimal spraying parameters should be spraying flow rate at 375.20mL/min, spraying distance of 1.72m, sprayer forward velocity of 0.14m/s and angular swing speed of 16.19(°)/s, then the coefficient of variation of droplets distribution of 11.471% was obtained.