The excavation for upper inclined shaft of water diversion system of Baoquan Pumped-storage power plant revealed that in the elevation of 668.000~651.000 m and 526.000~514.000 m, the ancient weathering crust was separately drilled through. The rock in ancient weathering crust is rather broken with much slob, bedrock fracture, abundant groundwater and large pervious rate. Grouting of ancient weathering crust becomes the most important step in inclined well excavation, and directly influences the safety and steady operation of pumped-storage power plant.