Abstract: Based on elasto-plastic damage theory of rock materials,the failure and fracture processes of rock slopes arenumerically simulated with the site response of the rock slope under strongseismic loading, including the local damage evolution and the developmentof failure area. Two independent damage variables are introduced into theconstitutive model to control the tension and compression behaviors of therock materials. Although the characteristics of initialmicro-cracks inherent in the rock materials are not considered in theconstitutive model, their influence on the properties of rock materials istaken into consideration by reducing the corresponding moduli andstrength. The interfacial characteristics between large cracks such as faultsare considered as in the interface contact.The numerical simulation by finite element method is carried out for thefailure of a practical rock slope on the left bank of a river with alarge hydraulic power station under a strong seismic loading (in100-year recurrentperiod and over a probability of 2\%). The mechanism of landslide for suchkind of fractured rock slope is analyzed. Some advices are proposedfor prevention and treatment of the landslide according to thesimulation results.