Abstract: In this paper, a micromechanical theory is used to study the nonlinear vis-coelastic constitutive relation of high rigidity particulate-filled polymers. It is demonstrated that the linear Eshelby's equivalent inclusion method and the relevant macroscopic average method can be generalized to research the constitutive relation of the composites, when the deformation of the materials is describled with linear strain and the particle's rigidity is very much higher than the matrix's.