Abstract: The determination method of porous medium permeability in the goaf is studied by FLUENT numerical simulation, and the built three-dimensional model is verified through the introduction of ventilation resistance laws. The paper summarizes and analyzes the hulking coefficient of coal and rock collapsed from the x, y, z three directions respectively, and the three dimensional continuous distribution functions of the goaf permeability and porosity is determined. It takes the stope space as a porous zone that has a different permeability, and it builds a more accurate working face—the goaf continuous flow field mathematical model. The paper introduces the ventilation resistance characteristic, and compares the numerical simulation with the resistance coefficient model based on the field test differential pressures and air quantity. The study is based on the Shaqu Mine 14204 fully mechanized working face, and combines with the field test data to make the numerical simulation validation. The results show that the model is effective and reliable.