Taking a typical landslide in Guizhou Province as the research object, the cause of the landslide was investigated. The yaahp calculation software and analytic hierarchy process were used to quantitatively analyze the cause of landslide, and the main causes and influencing factors of landslide were identified. The results show that this is a composite landslide, and the rainfall is considered as the main cause to induce landslide. The result can provide reference for the identification of this kind of landslide.