Firstly, according to the production process of liquid filling products, the overall structure and main parameters of the multi-station rotary capping machine are designed, and the assembly drawing is drawn. Then, the contour curve of the cylindrical CAM of the capping machine is designed through calculation, and the curve is optimized by using the quintic polynomial fitting. Finally, the three-dimensional solid model of the CAM is established in Solidwork. The results show that the actual production efficiency of the multi-station rotary capping machine can reach 14 000 bottles per hour, the operation is stable at high speed, and the noise generated by the machine is relatively small, which meets the requirements.