It is an issue to choose an appropriate capillary pressure-saturation curve in the research of seepage in unsaturated fractured rock mass. Based on the characteristic of the unsaturated fractured mass, the research on the capillary pressure-saturation curve in unsaturated fractured rock mass is summarized. The results show that seepage in an unsaturated fractured rock mass has some special characteristics including capillary flow, film flow, preferential flow, fracture-matrix interaction and channel flow; three methods to establish the capillary pressure-saturation curve include physical experimentation, numerical simulation and mathematical computation. All the results of these methods are also summarized. Finally, according to the characteristics of the seepage in unsaturated rock mass and all these results of the capillary pressure-saturation curve, the following results can be concluded: (1) there is no capillary pressure-saturation curve which can reflect the other characters of the seepage in unsaturated rock mass except the capillary flow; (2) it is a convenient method to build the capillary pressure-saturation curve by numerical simulation and mathematical computation; (3) the capillary pressure-saturation curve simulated by Brooks-Corey (BC) model is better than the curve by van Genuchten(VG) at initial stage during drainage, but worse at last stage.
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