The work aims to design a gas flow controller based on the internal sliding mode principle, so as to improve the stability and the precision of gas flow control in gas transferring and packing. The basic structure and packing flow of the box-type gas transferring and packing machine were introduced. Aiming at the non-linearity and hysteresis of the aeration process, an internal sliding mode control system was proposed. The control system included:control module, flow detection module and execution module. Based on the sliding mode control, the time delay caused by pure lag was eliminated by the predictive compensation model, and the improved sliding mode control equation and sliding mode surface were given. Finally, the experimental research was carried out. The verification results indicated that compared with the sliding mode control, the adjustment time needed by internal sliding mode control for gas flow control was only 1~3 s, and the reduction range reached more than 90% without overshoot. The actual control accuracy reached ±0.8 mL/min. The internal sliding mode control has the advantages of faster response speed and higher control precision, thus having better effect on gas flow control.