Abstract:In July 2020, two large-scale geological disasters occurred in Qianxi City, Guizhou Province, one of them is the Cangbaotian landslide. The deformation and failure characteristics of Cangbaotian landslide are different from those of the gently dipping red-bed landslide in Sichuan Basin. In this paper, by means of detailed field investigation, deformation monitoring and drilling sampling, the deformation and failure characteristics, deformation sequence and monitoring curve variation characteristics of the landslide are studied, and the formation factors of the landslide are analyzed. The research results show that the landslide is a large displacement landslide with a scale of about 8 million m3, and two secondary sliding bodies with different deformation rates and displacements are formed after deformation and failure. After the front edge of the landslide is stabilized, the back edge continues to slowly deform. The deformation failure is mainly affected by the cutting of valley in front, the result of loose broken rock and soil mass, and the softening of the sliding zone and increasing of the weight caused by continuous heavy rainfall.