One of the key factors of the air-based boost-phase TBM defense is the interceptor speed. Based on the analysis of both the interception process and the boost-phase TBM characters, an interceptor speed requirement model is established. According to the average speed model, the factors influencing the interceptor speed can be divided into two major kinds: the changeable and the unchangeable factors. Lastly, a quantitative analysis of the influence of different factors on the average speed is made. The conclusion of the research can provide a quantitative basis for the feasible analysis of air-based boost-phase TBM defense and the requirement demonstration of interceptor.