Abstract: An enhanced finite element model considering interface slips of composite beams was developed in this study by separating mathematical and physical meshes and introducing zero thickness interface elements to simulate discontinuous deformation of the interfaces. With separated mathematical and physical meshes, the overlapping of mathematical and physical elements in space was no longer required, and the sizes and shapes of mathematical elements can be chosen according to the mechanical descriptions of the physical elements. In each mathematical element, the physical area can be divided into multiple sub-domains. Each sub-domain can have different materials and geometry shapes, and can also have different mechanical characteristics, thus greatly reducing the number of mesh elements. Deflections, interface slips and the stress distribution of controlling cross-sections corresponding to a slip modulus increasing from zero to infinite can be easily obtained. In addition, a slip modulus range with a maximum extent of contribution to the composite beams can be directly determined. The proposed method is of high computational efficiency, and can be used in engineering practice involving complex structures, especially large-scale bridges subject to complicated loadings.