Abstract: During the development of electric thrusters, the trilinear pendulum are used to measure the micro-thrust. This paper, based on the principle of the micro-thrust measurement, firstly analyzes the damping characteristics of the trilinear pendulum measurement structure and its influence on the measurement result, then proposes a method applying external an damping to shorten the dynamic response time. The measurement system with external damping is analyzed. Lastly, the effectiveness of the damping control method is verified by simulation and experiment.