Abstract: Mass transfer is included in the flow of a gas-liquid mixture through porous media with phase change. In this paper, taking the physical and practical condition into account and with a simplification of formula, using a model of ideal porous media and local equalization method. A simple dynamic equation and the relative permeability formula describing the flow of gas-liquid mixture through porous media is derived based on the theories of mass conservation and momentum conservation, and dimen-sional analysis. It is pointed out that description of the flow behavior of such a type by Darcy's law and a conventional relative permeability curves is not satisfactory. The studies show that the equations are useful both theoreticallv and partically.