The work aims to design an express package clamping device to achieve the function of machine-assisted express packaging. After analyzing the current status of express package, the corresponding process of express package clamping device was researched, and a device with complex functions of clamping, lifting and rotating was designed. After movement and mechanics model of the device was deduced and established, the key parameters were determined. The simulation experiment was carried out by Adams and Matlab, and finally the physical object was developed and tested. Motion trajectory and speed of express package clamping device met the requirements. The packaging speed was about 16 s, shortening 63.3% of the working time. The packaging success rate was around 95.1% and the package continuous rate was over 96.0%. Through the design of express package clamping device, the clamping, lifting and rotating functions of the express can be achieved, with stable and efficient performances.