<p>Coastal protection structures have been widely developed using diverse engineering approaches to mitigate wave overtopping and enhance hydraulic resistance through increased surface roughness. This study examines the effectiveness of stepped embankment configurations in augmenting surface roughness and reducing wave overtopping rates. A series of controlled hydraulic model experiments were conducted to evaluate the performance of stepped-surface embankments in comparison with conventional smooth-surfaced configurations. Wave overtopping characteristics were systematically investigated under a range of wave conditions, with incident wave periods varying from 5 to 15&#xa0;s. The results demonstrate that the wave energy dissipation performance of both simple-stepped and composite-stepped embankments is strongly influenced by step height and geometric configuration. In contrast, smooth-surfaced embankments consistently exhibit the highest overtopping rates, indicating limited dissipation capacity. Based on the experimental findings, simple-stepped embankments are recommended for application in relatively shallow water conditions, whereas composite-stepped configurations are more suitable for deeper coastal environments, where enhanced dissipation is required. The study provides a scientific basis for optimizing coastal protection design by integrating hydraulic performance with considerations of environmental compatibility and structural resilience. Furthermore, the insights into wave–structure interactions over stepped geometries contribute to the advancement of more efficient and sustainable coastal engineering practices.</p>