In China, the fruit picking of sea buckthorn is mainly by the traditional artificial pruning method, which has greatly damaged the resources of sea buckthorn. In this paper, an air-suction plucking device with strong applicability, simple operation, stable and reliable was developed. Based on the mechanical system design of the plucking device, the flow field simulation and analysis software FLUENT was used to model and simulate the plucking device's air pipe ways, and the gas pressure and velocity transformation diagram in the air pipe ways were obtained, and the optimal working parameters for plucking sea buckthorn fruit were determined. It provides the index parameter basis for the further design of air-suction sea buckthorn picking device.