Abstract: In the process of open-pit mining, most of the rocks are broken by cast blasting and blasting vibration has a threat to the safety of the slope. Aiming at the stability of the bench slopes affected by blasting vibration, the dynamic response law of the bench slope under the two different conditions of back wave and head wave is studied by FLAC3D numerical calculation in combination with the practice of the north end slope project of Harwusu open pit mine. Finally, the dynamic response mechanism of bench slopes is analyzed.The results show that the bench slope of open-pit mine presents the elevation amplification effect under the influence of blasting vibration, and the peak vibration velocity of the surface and internal particles of the bench slope generally presents the trend of gradual attenuation with the increase of distance. The vibration velocity of particles in the same step decreases from the surface to the interior of the slope. The closer to the surface of the slope, the greater the vibration velocity of particles. In the case of back wave, the most significant elevation amplification effect is the bottom step, and the elevation amplification effect of particles in the same step weakens from the surface to the interior of the slope. In the case of wave front, the most significant elevation amplification effect is the top step, the same step of the particle elevation amplification effect does not show a significant trend of change.