Abstract: Basic principles and research status of stereo lithography apparatus was introduced，and research and development characteristics of unmanned aerial vehicle（UAV）plant protection spray head was analyzed.Fan shaped sprinkler commonly used in plant protection of UAV was prepared by stereo lithography apparatus，and a spray performance testing test-bed based on laser particle size analyzer was built.Experimental data showed that performance of fan-shaped nozzle based on stereo lithography apparatus met requirements of spray work.Stereo lithography apparatus would change design process and ideas of traditional plant protection sprinkler，improve research and development efficiency of UAV plant protection sprinkler，and promote manufacturing level of UAV plant protection sprinkler.