Based on the analysis of geomorphologic features, site investigation of old-aged landslide features, geological environmental conditions for landslide developing and deformation monitoring to the landslide, Xujiadong slope is congnized to be an old-aged landslide. Optimum design is presented on the basis of the analysis of the slip soil shear strength characteristic and sensitivity of slope stability to underground water level. It is applied in engineering practice, and improve both the reducing engineering cost and the insuring purpose of landslide correction, can be a reference for the other landslide investigation and correction.