Abstract: The deformation of porous media isvisco-elasto-plastic, with the elastic deformation as the main-bodydeformation, the viscousdeformation as the structure deformation and the plastic deformation as the damagedeformation. Based on the concept of effective stresses and theprinciple of damage mechanics, this paper studies the properties of effectivestresses of porous media. Assuming that the grain is in compression, and thegrains can have a local failure, with an increase of the effectivestresses and the supportingcapacity of grains, the damage effective stressesare considered in the calculation, which would show the complex properties of deformation ofporous media more accurately.