At present, the study on mathematical model of seepage system of rock mass focuses on the model of seepage in fractures. It includes four kinds of seepage models, which all adopt the theory of continuum seepage. Therefore the simulation of noncontinuum seepage in natural rock mass is not accurate. Also, because it is hard to determine the parameters of rock mass model, the reliability of these seepage models is doubted. The triplemedia (holes, fractures and blocks) coupling seepage model is presented in this paper, which can improve the reliability of seepage simulation.