Abstract: Taking the Hongshiyan slope as the research object, combined with microscopic crack development, the discrete element method is used to study the initiation mechanism and failure process of Hongshiyan slope under seismic dynamics. The results show that with the seismic wave input, cracks develop rapidly in the weak interlayer areas due to low strength. Hongshiyan slope shows a progressive failure and collapse process of "layer-by-layer peeling off", and the disintegration phenomenon is more serious. The displacement of particles on the air-facing surface is larger. The larger the buried depth in the same vertical direction inside the slope, the smaller the particle displacement. The variation of particle velocity is closely related to the time history of the seismic waves, and the velocity curve is basically consistent with the shape of waves.