This paper applied the Pro/E behavioral modeling technology in the optimization design of packaging machinery spare parts, in order to get the optimal design parameters. The general process of Pro/E behavior modeling was briefly given, measurement features of plug-in boards drive mechanism model were established namely, movement analysis characteristics and relationships analysis features, were inserted for sensitivity analysis. On the basis of feasibility/ optimization analysis, the large diameter and small diameter of the cam, cam position and the distance between the holes of the crank in the plug-in boards drive mechanism were optimized. As a result, the parameter sizes of the plug-in boards drive mechanism model which satisfied the design intent were obtained, after rounding, the cam large diameter R was 34 mm, the cam small diameter r was 30 mm, the height of cam H was 40 mm, and the distance between the crank hole L was 91 mm. In conclusion, application of Pro/E behavioral modeling technology in the optimization design of packaging machinery spare parts could greatly improve the design efficiency and quality of packaging machinery.