The dynamic characteristics of a balance valve used in crane lifting system were analyzed, the working principle of the balance valve under different working conditions was discussed, and the factors affecting the stability of the system are comprehensively analyzed. The influence of the diameter of the damped hole and the section gradient of the valve port on the flow characteristics of the balance valve was analyzed. At the same time, the structural optimization scheme was proposed. The simulation and test results show that reducing the diameter of the damping hole of the balance valve could obviously increase the stability of the system, but too small diameter will increase the throttling loss and affect the efficiency of the system. Through structural improvement, the dynamic characteristics of the balance valve could be effectively improved, and the pressure fluctuation amplitude of the system can be reduced when the load drops, thus providing a reference for the design and improvement of the balance valve.