Abstract: A micromechanical model was proposed to estimate the overall nonlinear viscoelastic behavior for the particulate polymer composites. The method was based on the generalized secant method and Laplace transform technique. Schapery's thermodynamics constitutive law was used to simulate the experimental data of high-density polythene (HDPE) matrix and the material functions were identified. The stress and strain relation at a constant strain rate for HDPE-matrix composite filled with glass beads was analyzed. The predicted results agree well with the experimental ones. The results show that the GB/HDPE composites present obvious nonlinear behavior . The model can well predict the nonlinear viscoelastic properties for polymer composites.