Aiming at the problems of long stability time and large steady-state error of flow online detection in pneumatic conveying system, a flow control method for pneumatic conveying is proposed. On the basis of analyzing the pipeline pressure, flow velocity and material particle group conveying characteristics, the mathematical model between the pressure difference change and the flow rate of the system flow under equilibrium conditions was established, and the fuzzy control method was introduced at the same time, and the fuzzy PID controller was designed, flow control system. The simulation analysis is carried out with Matlab/Simulink as the platform. The experimental results show that the designed flow control system can well realize the fast, stable and high-precision detection of the flow of the pneumatic conveying system.