Abstract: Based on Zhangjiagou landslide in Qingchuan, in combination with the engineering geological conditions and deformation and failure characteristics, the paper analyzed the deformation failure reason and stability in detail, revealed the relevant control engineering measures, and numerically simulated before and after the control engineering measures by FLAC^3D. The results show that the morphological characteristics of the landslide and the loose structure characteristics of the soil-rock mass are the prerequisite of the landslide instability, while the change of geological environment caused by rainfall is an inducing factor of the landslide instability. The further deformation of landslide is effectively controlled by the control measures which mainly rely on sheet-pile retaining wall and drainage engineering and the stability of the landslide is ensured. The result of numerical simulation is identical with the actual deformation and control effect. It not only verified the effectivenes of the control engineering measures of the landslide, but also showed the rationality of the numerical simulation results.