Abstract: With a special kind of beam with two holes, a substructure method for creation of its finite element model is presented in this paper. The division and discretion of the substructure, the definition of boundary freedom and the forming of reduced model are introduced. According to the requirement of displacement coordination when linking with general beam element, the reduced model is transformed into a special kind of beam element, which has the same number of nodes and the same property of node freedom with general beam element. The substructure modeling method can simplify the model and its calculation greatly.