The work aims to design a labeling control system, so as to improve the automation degree, labeling speed and precision of packaging machinery labeling process. A labeling control system was designed based on machine vision which mainly included PC, industrial camera, visual processing module, motion control module, printer, labeling machine, label detection module, etc. The image processing algorithm was emphasized, in which the soft morphological filtering and edge detection were used for labeling region recognition and location. Template matching was used to detect the flatness and inclination of labels. Finally, an experimental study was carried out with cube, round and irregular packaging cartons as research objects. Experimental results showed that, the average positive calibration rate of the proposed labeling system was above 99%. The labeling system of packaging machinery based on machine vision can meet the packaging requirements, improve the automation level of packaging machinery, enhance packaging efficiency and reduce enterprise costs.