The work aims to integrate CAD technology into the design of packaging machinery conjugate cam mechanism. It discussed the theoretical basis for the design of the cam mechanism, and analyzed, solved and simulated such a mechanism by examples according to a given follower motion rule and based on SolidWorks software, Motion plug-ins and Excel software. The accuracy of the design was rounded off to 3 decimal points. The simulation results accorded with the solving theory. In conclusion, the designed method is simple and accurate. It can avoid tedious calculation and solve problems with the design and simulation of such mechanism.