Hydraulic fork lifting platform is a practical tool applied in orchard for picking.In this paper,the mechanism was taken apart into different component modules on the basis of its structure,the theoretical expression for load change of working actuator in the system was deduced.For the mechanism in orchard has to accomplish operations such as lifting and leveling,which requires high efficiency and good safety performance.The principle diagram of the hydraulic system was formulated and the char-acteristics of the hydraulic system were analyzed.What is more, the hydraulic components were calcula...