Abstract: Coal containing gas is a kind of complicated mechanical medium, the coal mine gas changes the coal physical and mechanical properties and has a positive role on the coal blasting. The coal will be deformed and the occurrence state of gas will be changed under the blasting action, and then the porosity of coal will be changed correspondingly. Based on the Taylor method, we defined blasting damage variable by the porosity of coal and studied the damage evolution equation, then determined the constitutive equation and the blasting damage model of coal containing gas according to the effective stress principle.