<p>The seismic failure mechanisms of high-steep, anti-dip rock slopes common in southwestern China are poorly understood, posing significant challenges to disaster risk management. This study combines physical shaking table tests and numerical simulations to investigate the dynamic behavior of a representative conceptual model derived from field surveys in the Jinsha River basin. Analyses were conducted under various Peak Ground Accelerations (PGAs), loading directions, and interlayer configurations. Results reveal a progressive five-phase failure evolution: initial microcracking, crest tensile failure, shoulder collapse, sliding surface development, and overall instability. Seismic amplification under Wenchuan wave excitation was significant in two distinct zones: a near-surface layer and the middle-to-upper slope body. While horizontal amplification showed a consistent elevation effect, vertical amplification was frequency-dependent, shifting from a surface to an elevation effect with increasing frequency. Most notably, weak interlayers decisively enhanced seismic stability. They served as energy dissipation and wave attenuation media, and increasing their number markedly reduced the range and magnitude of slope deformation. Our results suggest that weak interlayers, often considered a destabilizing factor, can paradoxically improve the overall seismic stability of anti-dip rock slopes.</p>