Borehole acoustic testing is a comprehensive testing program that utilizes ultrasonic characteristics such as changes in acoustic wave bands, comparative analysis of waveforms, and energy attenuation in the rock mass to determine the structure, strength, macroscopic defects, and physical properties. Using the acoustic principle to test the rock mass within a specific depth range in the borehole, the test results combined with the on-site geologic description and laboratory rock mass results to establish the relevant geologic model, which can quickly get the integrity, physical properties, and mechanical parameters of the dam foundation rock mass. The application of quantitative indexes provides a more accurate and reliable basis for the determination and optimization of foundation rock mass, which can quickly respond to the design technical requirements, reduce the amount of excavation, reduce the amount of concrete pouring, and have an essential role in promoting the shortening of the construction period and the reduction of the cost, and this kind of research provides a reference case for the optimization of the excavation of other dam projects.