Abstract: The control methods of air compensation through the end of main duct and coverall air compensation with fixed volume through bypass were introduced and their merits and demerits were analyzed.The principle of controlling grouping supply of cut tobacco in pneumatic feeding was put forward.This control system adopted S7-200, S7-300 PLC, MP370 and Profibus from Siemens.Once the control system was used, the air velocity in the pneumatic feeding system was controlled at (17.5±1.5) m/s, the power of fanmotor and frequency converter reduced from 55kW to 37kW.The system ran stably, the running cost reduced, and energy saving reached about 30%.