利用ＬＭＴＯ－ＡＳＡ方法研究了Ｃ１１＿ｂ晶体结构的ＭｏＳｉ＿２三种（００１）表面电子结构，分别给出了三种不同表面总体态密度和表面层原子局域态密度及分波态密度，与体结构相关原子态密度作了对比，并对费密能级上的态密度作了比较讨论。就表面稳定性而言，以Ｍｏ原子为表层原子的表面结构最不稳定，以单层ｓｉ原子为表面的表面结构最稳定，该结论支持了Ｔ．Ｋｏｍｅｄａ等的实验结果￣［１５］。 The electron structures of three kinds of (001) surfaces of MoSi_2 with C11_b crystal structure were studied by using LMTO-ASA method. Three different surface total density of states and local density and partial density of surface atoms were given respectively, which were related to body structure Atomic density is contrasted, and state density on Fermi level is discussed. In terms of surface stability, the surface structure with Mo atoms as the surface atoms is the most unstable, and the surface structure with the monolayer Si atoms as the surface is the most stable. This conclusion supports T. Komeda et al’s experimental results [15].