Abstract: This paper studies on the basement of the characteristics of the geology and deformation of the Tumenzi landslide, then do further research on the genetic mechanism, deformation failure mode as well as starting mechanism. The research result shows as follows: first, the deformation mechanism of the landslide is Translational gliding mode; second, the landslide is in the stage of wholly creep deformation with partly slidingl third, the continually heavy rain is the main factor which may results in its broken. At last, put forward the disposing suggestions according to characters of the landslide, which has important significance in guiding the design and construction of this kind of projects.