Abstract: A new substrate strength calculation model for high-temperature and sweat-lubricating porous materials has been established by deducing its characteristic parameter of λ and traditional thin-walled honeycomb theory and it has been used to calculate the substrate strength of the order porous material with thick cell walls.The relationships among relative density,porosity and substrate strength were calculated and analyzed by using the model and taking the cermet as typical substrate material.The results show that the compressive strength decreased with the increase of the porosity and the relationship is consistent with traditional empirical value.The elastic modulus of the material decreased with the increase of the porosity,and the decreasing rate was larger within the porosity range of 0.6 than that beyond of the range;Poissons ratio of the material increased with the increase of the porosity,and when the porosity was larger than 0.4,the increase showed a higher rate.