Abstarct: Abstract: In coastal regions, the swash zone is of significant importance due to the interactions between coastal currents, groundwater, and sediments. Therefore, numerical modeling of hydrodynamic-morphodynamic processes is essential. baxsed on the evaluation of the XBeach model, it is determined that this model has a high capability in simulating coastal hydrodynamic-morphodynamic processes. This study aims to assess the performance of the XBeach model in modeling the swash zone of coarse-grained and coral coasts, conducted in three main sections: 1) Evaluating the performance of the XBeach model in modeling coarse-grained coasts, 2) Developing the XBeach model to address the model’s phase error, and 3) Assessing the performance of the XBeach model in simulating coral coasts. The evaluation of the XBeach model’s performance and its two modules, SB and NH, in simulating swash processes, comparing the results, and sensitivity analysis are highlighted as the study's research gaps. The first part of this study numerically reconstructs three different laboratory experiments to assess the XBeach model's performance in simulating coarse-grained coasts. The results indicate that the XBeach model performs acceptably in modeling hydrodynamic and morphodynamic processes in the swash zone, with the NH module outperforming the SB module (with 5% less error). Additionally, the results show that the phase error during infiltration/seepage into the aquifer in XBeach leads to the propagation of numerical modeling errors in calculating bed profile changes and aquifer water level. Despite the advancements made in the development of the XBeach model, it still requires further refinement and currently exhibits weaknesses in modeling the interactions between groundwater levels and seawater movements. In the second part of this study, an algorithm was developed to address this deficiency by evaluating the modeling process in the XBeach model, leading to the further development of the model. To evaluate the performance of the developed model, six laboratory tests were simulated using both the original XBeach model and the developed model. The results indicate that in the developed model, the mean error in coastal morphology changes was reduced to less than 5%, whereas the error values baxsed on the original XBeach model were approximately 10%. Additionally, the results revealed that the modeling error in approximating aquifer levels baxsed on the original XBeach model was around 8%, while in the developed model, this error was reduced to less than 3%. The findings of this study demonstrate that the developed model successfully addressed the phase error present in the original XBeach model and accurately simulated the hydrodynamic and morphodynamic processes in the swash zone. In the third part of the study, the performance of the XBeach model in simulating coral coasts was evaluated. In this section, after assessing the influential parameters and prevailing conditions in coral coasts, a laboratory model was examined and numerically simulated using the XBeach model. The results showed that with precise modeling and the use of appropriate parameter values, the numerical modeling error was 4.78% (less than 5%), indicating an acceptable level of accuracy in the numerical model for simulating hydrodynamic-morphodynamic processes in coral coasts.