Taking the underground cavern group of Dadu River Jinchuan Hydropower Station as the research object, the key technology of deformation monitoring, early warning and safety control of hydraulic tunnels in extremely fractured rock mass is systematically studied by theoretical research, on-site monitoring and numerical computation, the characteristics of the surrounding rock of hydraulic tunnels and stability of the import and export slopes are investigated, and the safety coefficient of the side slopes and danger of slope rockfall are evaluated under multiple conditions, and the stress-strain characteristics of the surrounding rock during excavation of the tunnels and the sides of the side slopes under the condition of extremely fractured rock mass are simulated; On this basis, a monitoring system for hydraulic tunnels and slopes in extremely fractured rock mass is constructed, and an index system for judging the risk of surrounding rock stability is established; finally, an intelligent control system for underground cavern group construction based on BIM is constructed, and a platform for the safety and intelligent control of hydraulic tunnels is set up. The results show that the system improves the accuracy of construction risk identification of hydraulic tunnels in extremely fractured rock mass, realizes comprehensive and efficient real-time monitoring of project status, and provides a scientific basis for safety control of tunnels and slopes.