According to the arrangement of micropiles，the micropile system used to reinforce bedding rock slope can be classified into three types：independent micropiles system，planar truss micropile system and spatial truss micropile system. On the basis of combining the mircropiles and the rock mass among the micropiles as a whole structure，a new analytical model of micropile system is proposed. The interaction between the micropiles and rock mass can be simulated with this model. The mathematical and mechanical model for the internal force and deformation of the micropile system is established by finite element method.