A numerical calculation method and a new type element of EFM for the simulation of the RCC dams is presented. It takes into account the more relevant features of RCC, such as the transversely isotropic, the layered character, the strength unequal to tension and compress and the discontinuities. A 3D model of RCC Dam, built in South-West of China, is used to perform the corresponding analyses. The result shows the location of third height to dam heel in upstream dam will be crack between layers. So it is very dangerous for arch dam. In the the locations of third height to dam toe and dam crest of the downstream of the dam will occur the stresses concentration, so some of engineer measures must be adopted to avoid the damage.