Abstract: A new mechanical model is established in this paper on the basic theories of fracture mechanics and meso-mechanics. The mechanical properties of porous media are analyzed. Based on the geometric descriptions and morphological parameters of the pores in porous media such as porosity, shapes and scales, effective elastic equation can be established by equivalent inclusion theory. The final variables of effective elastic equation are stress, strain and morphological parameters of the pores. Mechanical energy, elastic strain energy and potential energy of the porous media are calculated and the energy conservation equation is established. The final variables of energy conservation equation are also stress, strain and morphological parameters of the pores. So the stress-strain relationship of porous media can be obtained by the two equations. Applying the mechanical model in cement material, the mechanical properties can be calculated. The results obtained are consistent with conclusion of the literatures.