Abstract: Impulse coupling effect of short pulsed laser ablation the target has great application in the fields of laser orbital debris removal. High precision impulse measurement is the necessary method in studying the impulse coupling effect. Based on the impulse measurement background in laser orbital debris removal, the torsion pendulum method was analyzed, the response equation was obtained in the situation of pulse micro thrust interaction. All these will provide the research basis for the design of measurement system and experimental research. According to the actual circumstance, that was the space debris ablated by a certain frequency laser pulse, the simulation analysis of response characteristics of torsion pendulum was conducted by multi-pulse micro-thrust. The conclusions are as follows:the system response curve is a sine curve and the vibration amplitude attention depends on the damping ratio; the impulse amplitude depends on the pulse force; when the force interaction time is less than the 1/8 of the torsion period, the force can be considered as an instant impulse effect; in this situation, the response effect is almost the same when the total torque is the same, although the number of pulse force is different. The system error is concerned with damping ratio and the ratio of the force time and the torsion period.