A synthetical analysis on utilizable foundation rock at the toe-plate of dam is conducted by several kinds of methods, e.g., project analog study, analyses on results of rock mechanics properties for existed dams, sonic wave tests for rock mass at the toe-plate area, deformation tests and quality assessment for the rock mass, the standard of utilizable foundation rock at the toe-plate of concrete face rock-fill dam of Shuibuya Project is determined. The acceptable standards of utilizable rock mass in which sonic wave speed through hard rock equals 3.8 km/s and that through soft rock 3.2 km/s are proposed. The weak unloaded zone of rock mass may be taken as rock base-plane of the toe-plate for Shuibulya Project.