The article is devoted to the development of a method for assessment of the effective deformation properties of the polymeric hyperelastic composites with the interphase contact layer. The dimension of contact layer is determined by scale factors (i.e. a characteristic dimension of the inclusion of micro-sized mineral filler, which is a composition of micro-sized particles and aggregate assembly of nanoscale particles, or properly of nanoscale particles of filler) and by the surface structure that determines the dimension of contact layer. Identification of the surface properties is performed by the method of fractal analysis that allowed to calculate the fractal dimension of the filler surface on the basis of experimental data and to estimate the size of the interphase layer. Identification of the properties of the hyperelastic matrix is carried out on the basis of a family of potentials that take into account the effect of the polymer material stiffness changing under tension. A numerical method for determining the effective mechanical properties of hyperelastic composites with dispersed spherical filler is formulated. This method is based on the solution of the series of periodic problems on the cell with the inclusion, which simulate conditions of uniaxial tension and pure shear deformation. Based on this technique and related experimental data of properties of filler, matrix and contact layer obtained in IPRIM RAS, it was shown that the shungite filler of micro- and nanoscale dimension increases the effective rigidity of the composite material. These calculations have also shown that in elastomer composites the matrix is more rigid than in the “pure” material, which is used as a matrix in the production of such composite materials.