In this study, a unified method was proposed for the analysis of rainfall-induced landslides by using GIS based landslides prediction model (YS-Slope model) and a prediction method by using a large deformation analysis method. A susceptibility assessments of landslides and debris flows in Umyeonsan (Mt.), South Korea were conducted as a case study by using the landslides prediction model and ABAQUS/CEL large deformation method. It is shown that the result of the analysis has a good agreement with historical landslides and debris flows. Based on the case study for Umyeonsan (Mt.) landslides, failure behaviors of landslides and debris flows are well predicted by the method described in this study. These procedure can be apply to the prediction of landslides and debris flows of another study area.