Finite element method based on interfacial debonding Voronoi cell, including random information of inclusion distribution, is more efficient than displacement finite element method in simulating multiphase composite. The finite element method based on interfacial debonding Voronoi cell was used to simulate the representative volume element(RVE) to obtain the stress field. And then the average stress-strain curve, which can reflect the influence of the interfacial debonding on the effective properties of the materials, and effective elastic modulus were obtained by using the direct homogenization method. We simulated several models using the program which can simulate the representative volume elements containing arbitrary inclusion on a large scale, and analyzed the influences of the shape, the volume fraction and the spatial distribution of inclution on the effective elastic modulus of the material. The results show that the model which has a large effective elastic modulus generally has a strong stress concentration at the interface, and the interfacial debonding occurs earlier during the loading process.