Abstract: The edge area of Qinghai-Tibet Platean in Southwestern of China is famous for its abundant water-power and will be an engineering construction center,. Because of complicated and intense intrinsic-extrinsic dynamical geology action, high and steep rock slopes are well developed in the area. These slopes show some distinguished characteristics. They are different from general rock slopes because of the special geological background. According to the data from field investigation, these slopes can be characterized as super height, high geostress and complicated deformation and failure evolution process. The deformation and stabilization of slopes decide whether a project is feasible, affect the time limit for a project and control the construction cost. This paper points out that the deep fractures are the result of the coupling of endorgenic and exogenic geological processes by unloading of river valley and releasing of high geostress. The slope structure, strong geostress, rock property and high steep topographical features provide material foundation for deep fractures. Finally, the paper studies how deep fractures affect human engineering construction, and analyzes how these fractures influence the leakage of reservoir and the stability of slope. The prestressed anchoring cavern and other mountain reinforcement methods can be used to tackle deep fractures.