Abstract: The Hetaoping landslide is located in Qunlian Village, south of Shanshu Town, Yinjiang Tujiazu Autonomous County of Guizhou Province. After the first sliding in June 2008, the deformation of the landslide suddenly increased followed by the continuous heavy rainfall in 2014 flood season，seriously threatening the lives and property safety of the residents of Hetaoping Group. Therefore, it is necessary to study the mechanism and stability of the landslide, providing a basis for the subsequent landslide prevention and control. The geomechanical mechanism and the stability of the landslide deformation and failure are studied by applying comprehensive research methods such as the field investigation, the geological analysis and the numerical simulation. The results show that the terrain conditions of the Hetaoping landslide area, such as steep slope above and gentle slopes below, as well as the thickness and strength of the covering layer, are the material conditions for the formation of the landslide. The extensive and long rainfall duration are important triggering factors for the formation of the landslide, and are also the main controlling factors for the development of the landslide deformation. The instability mechanical model of the Hetaoping landslide is pushtype landslide, which is currently in the stage of basically stableunstable creep deformation. The stability of the Hetaoping landslide is satisfactory under natural conditions, but the stability of the landslide is in an unstable state under continuous rainstorm conditions.

Key words: Landslide, Mechanism Analysis, Numerical Simulation, Stability Evaluation