<p>The mechanical properties of rock structural planes exert a significant influence on the seismic performance of rock slopes. Although laboratory tests have confirmed the dynamic degradation of shear strength along rock structural planes under cyclic loading, most existing studies characterize this behavior using the traditional Coulomb-slip model, assuming constant shear strength throughout the analysis. To overcome this limitation, this study introduces a numerical framework for simulating the seismic displacement and failure characteristics of rock slopes accounting for the dynamic degradation of rock structural planes. It is then employed to systematically investigate the influence of dynamic degradation of sliding surface on the seismic displacement and failure characteristics of rock slopes, with particular attention to their response to pulse-like ground motions. The results show that accounting for the dynamic degradation of rock structural planes increases the seismic displacement of the slope case by approximately 54%. Moreover, compared to non-pulse-like ground motions, pulse-like ground motions induce significantly larger seismic displacements—up to about 13.3% greater of the slope case. These findings could hopefully assist in assessing the seismic risk of rock slopes subjected to strong pulse-like ground motions.</p>