Abstract: When carton blank travels and falls in the lower channel in YB65A cartoner, it may be out of position because of dither or bending, which results in conveying delay, carton blank jam or falling out, and the carton quality is deteriorated. Therefore, a method of guiding the blank in the lower channel by means of compressed air was developed. The compressed air pipes were installed at the fixed upper folding plate and the upper guide of pre-folding chamber, aided by compressed air, the blank was guided to blank grippers. An electromagnetic valve was used to accurately control the on/off of the compressed air. The application results showed that the quality problems caused by the dither and distortion of carton blank in lower channel were well resolved, the adaptability of the cartoner to carton blank, the stability of blank feeding were improved, and the machine efficiency increased by 0.4 percentage points.