Abstract:In recent years,with the construction of the expressways,large-scale hydro projects and deep foundation pit projects,accidents arising from cut are more and more serious,especially in West of China,where ground surface is mostly covered with colluvial soils,and the human activity has already become the main inducing factor on geologic hazard. In order to understand the fundamental mechanism of cut-induced landslides in colluvial slope and to clarify some important characteristics of slope,in-situ cut tests and synthetic field monitoring method were carried out on a typical colluvial slope in Guizhou Province,China. The results demonstrate that most of accumulation landslides caused by cut are shallow drawing slope failures. The deformed zone lies within the top soil layer of 4 m,the deformation amount of slope surface is the biggest,and the deformation form is relaxation,which is reduced from the top to deep part of slope gradually. The alert height of the free face is 3 m in such slope. When the free face exceeds 3 m,proper protecting measures are necessary. Under the influence of strong rainfall,the uncovered colluvial slope after cut easily leads to collapse accident.