Abstract: It is regulated in Code for Engineering Geological Investigation of Water Resources and Hydropower that the bearing capacity of hard rock and medium hard rock foundation can be valued by the reduced saturated uniaxial compressive strength. The bearing capacity of hard rock foundation is valued at 1/25 to 1/20 of the uniaxial compressive strength of the rock and that of medium hard rock is 1/20 to 1/10 of the uniaxial compressive strength. Based on the comprehensive analysis of the research results of different fields, the original valuing principle is deemed as conservative because it is unilateral to only consider the influence of uniaxial compressive strength,which may cause waste in practice. According to the characteristics of hydropower projects and research results of different fields, the valuing principle of bearing capacity of rock foundation which considers both the integrity and strength of the rock is proposed and it is advised that related specifications of the Code should be revised to meet the need of engineering practice of the current time.