Soft plastic composite film materials are an important component of pharmaceutical packaging, which can be used to package types of drugs such as powders, granules, and liquids. Among the numerous performance indicators of flexible plastic packaging, the friction coefficient has a significant impact on the material's machine performance and whether the packaging can proceed smoothly. If the dynamic friction force of the packaging material is too large, the resistance generated during the traction process of the packaging material is relatively large, which can easily cause the material to stretch, deform, or even be pulled apart. However, if the Stiction is too small, it is easy to slip during the traction process. For the formed soft plastic packaging bags, the friction between the inner materials will also affect the opening of the packaging bags, and larger friction will lead to poor opening of the packaging bags. Therefore, strengthening the testing of the friction coefficient of soft plastic composite film materials for pharmaceutical packaging is an important guarantee for the smooth progress of the packaging process. The friction coefficient of the inner and outer surfaces of the same packaging material is not the same, and the friction coefficient generated by the same material on different contact surfaces also varies. Therefore, when testing the friction coefficient of flexible plastic packaging materials, specific friction surfaces and friction materials should be specified based on actual usage.