It is difficult to simulate the whole process of rock slope deformation and failure, however, it is very necessary to do so in practical engineering. With the help of the FEM/DEM, the integrated single and smeared crack mode was adopted to analyze the initiation and propagation of the rock mass. Then, this model was checked by Brazilian disk splitting tests. Finally, a typical slope of Luo-Fu Highway was analyzed using the procedure. In case of storm and earthquake, partial slide or overall slide happens. In case of storm, partial slide happens; however, in case of both storm and earthquake, overall slide happens.