In order to improve the efficiency and accuracy of drug packaging and ensure the safety of drug production. On the basis of full study of the present situation of drugs packaging production line, machine vision is applied to automatic detection of drugs in pharmaceutical packaging production line. Based on the maximum entropy threshold, an image segmentation method is designed. At the same time, adaptive gaussian guided image filtering algorithm is adopted to design an image denoising algorithm. Through the algorithm simulation and experiment verification, this system can realize the automatic detection of the drug packaging production line, and can automatically eliminate the unqualified drugs and ensure the production safety. The automatic detection system of the drug production line in the paper has the advantages of high automation and high efficiency, and has a broad market application prospect.