Because of the humidity in the tofu factory, a pneumatic conveyor was designed to carry food boxes in the humid factory. The cylinder telescoped to provide power for the whole conveyor. In this study, the basic structure and working principle of the conveyor were described, and the velocity relationship between the input and output components was deduced for the need of equipment improvement and control. The working process of the conveyor was simulated by using the fluid dynamics simulation software flow 3D, which verified its practical feasibility and provided a data reference for the later electromechanical control.