Abstract: Laser displacement sensor has been successfully demonstrated to be a method for measuring separation time of pyrotechnic separator, the corresponding system to measure the separation time of explosive bolt has been designed and tested. It is shown that the measuring precision using new method is 0.184%. The tested average separation time is 14.74 ms, while that using traditional target-line method was 14.60 ms. Moreover, it has been revealed that the presented method is not only good at measuring separation time, but also an indirect way to analyze and evaluate pyrotechnic separator's characters, such as separation speed, separation acceleration and separation impulse.