Abstract: In order to explore the role of agricultural plant protection UAV in the prevention and control of major crop diseases and pests, Kunshan City has actively introduced plant protection UAV to carry out experimental demonstration of the prevention and control of major rice diseases and pests. The results showed that the control effect of plant protection UAV on rice leaf roller was 98.67%. The final control effects on rice planthpper and sheath blight were 83.57% and 89.78% respectively, which were lower than 96.43% and 98.07% of conventional plant protection machine. The control effect on rice stem borer is only 48.16%, which is far from 73.9% of the conventional plant protection machine. Pesticide plant protection UAV saves labor and cost, has good control effect, low dosage and high pesticide utilization rate, but it has high technical requirements for operators, high fuselage price and few professional maintenance points. It is suggested that the plant protection professional service organization should purchase, train professional operators, improve the socialized service ability, and further promote the unified prevention and control of crop diseases and pests in Kunshan.