The homopolar linear synchronous machine (H-LSM) with transversal flux is usually analyzed by three dimensional (3D) model based finite element algorithm (FEA), resulting in very high complexity and long time consumption. In order to solve such problem, one improved 2D FEA model is proposed in this paper. Firstly, the special topology and operation principle of H-LSM are introduced, and the equivalence principle is illustrated via magnetomotive force-permeance theory. Then, based on such principle, corresponding 2D FEA model is built by using equivalent multiple excitation windings, effective transverse length and suitable inter-pole gap length. Finally, the air gap flux density and no load back electromotive force (EMF) obtained from the proposed 2D FEA model are fully compared with those from 3D FEA model. Comprehensive results have demonstrated that the new model can almost get the similar accuracy with 3D model, while consuming less simulation time. Therefore, it is more suitable for the initial design stage and has great potentiality in practical application.