In this paper， the material point method was used to analyze the failure modes of slope， determine the slope models of shallow， middle， and deep failure modes by changing soil parmeters， and then analyze the failure process and change the law of three failure modes of slope under the consideration of soil strain softening model and different seismic loadings. The research shows that when strain softening is considered in the static calculation， the slope failure process is more complicated. After the sliding body slides along the sliding surface， the shallow failure body continues to break into fragments， the middle failure body continues to split into small blocks， and the deep failure body appears as a new layered failure zone. When strain softening is not considered in the dynamic calculation， the seismic loading does not change the failure modes of the slope but aggravates the slip and deformation of the slope and increases with the increase of the peak acceleration of the seismic loading. When strain softening is considered， the increase of peak acceleration of seismic loading changes the slope failure modes， and the friction Angle plays an important role in this process. The results can provide a reference for slope treatment and landslide prevention.