Abstract:In accorda nce wi th the speciali ties of selecting the o bjectiv e speed for high-speed railw ays concerned wi th many facfo rs including no t only the quanti ta tive facto rs but also the qualitativ e facfors, and combined with the compari son and the selection of the objectiv e speed for the Jing-Hu hig h-speed railw ay , a synthetic optimi za tion method has been proposed by applying a multi lev el sy nthetic ev alua tion digi tal model based on the fuzzy mathematics.