The work aims to study an auxiliary clamping device that can improve the efficiency of express packaging. By researching the process and method of express packaging, the designed lifting mechanism, clamping mechanism and rotating sealing mechanism were used to realize the work of express auxiliary packaging. Ansys and Matlab were applied to carry out simulation experiment to determine the feasibility of the mechanisms, make the physical prototype and carry out the field test. The results showed that, the packaging success rate was about 95.3%, which satisfied the actual demand of assisting the manual express packaging. The continuous rate of machine packaging was above 96.1%, and the working reliability of the device was high. Under the working condition of continuously packaging multiple cartons, the average packaging time for each carton was about 13 s, which reduced the time required for manual packaging by more than 55.3%. The express clamping auxiliary packaging machine is able to assist the staff in realizing the clamping work of express packaging, which can reduce the labor intensity of express packaging personnel and improve the work efficiency.