In order to study the seismic macroscopic failure process and dynamic response characteristics of rock slope with muddy interlayer and reveal the influence of muddy interlayer on slope stability, a similar slope model with concave and convex slope types was designed, and shaking table test was carried out; finite element analysis was used for numerical modeling analysis, and the results obtained by the two models were compared. The results show that: ① The macroscopic deformation and failure process of the model slope is divided into three stages. Muddy interlayer dislocates, and cracks occur; mud interlayer slips, and cracks expand; slope collapses; ② The seismic load has a decisive influence on the stability of the slope. With the increase in the seismic acceleration amplitude, the slope damage becomes more serious; ③ Muddy interlayer is the weak part of the slope. Under the influence of the earthquake, tension cracks first appear, which is a key factor in triggering the instability of the slope; ④ The seismic acceleration response characteristics of the two slopes are as follows: with the increase in seismic load, the peak ground-motion acceleration (PGA) amplification coefficient first significantly increases and then slowly decreases. The curve trend of the PGA amplification coefficient of the two slopes is basically the same. The values near the third interlayer and at the slope shoulder are significantly higher than other measurement points. The PGA amplification factor of the concave slope is slightly larger than that of the convex slope, and the trend of the broken line is more tortuous, showing a more complicated amplification effect; ⑤ Numerical simulation results show that when the seismic acceleration amplitude reaches 0.6g, the slope undergoes instability and failure. The failure modes of concave and convex slopes are slightly different. The failure mode of concave slopes is as follows: Slope shoulder collapse, with sliding failure near the point of gradient change. The failure mode of a convex slope is mainly the line of gradient change failure. Overall, the seismic stability of a convex slope is slightly better than that of a concave slope.