This study investigates the effectiveness of seagrass in attenuating wave energy, using a mathematical model based on shallow water equations. Seagrass meadows, known for their ecological benefits, are increasingly recognized for their potential in coastal protection. Our research focuses on understanding the dynamics of wave attenuation facilitated by seagrass through both analytical and numerical approaches. To begin, we derive the wave transmission coefficient analytically, providing a theoretical framework for how waves interact with seagrass beds and how certain parameters influence wave transmission. For a more comprehensive analysis, we employ a staggered finite volume method to solve the shallow water equations numerically, enabling us to simulate interactions between waves and seagrass under different environmental conditions. The numerical solutions are then compared to experimental data, which resulted in a good agreement between the two approaches, validating the accuracy of the numerical scheme. In addition, for a certain scenario, a numerical simulation was performed to observe the wave reduction rate due to the presence of seagrass. In this case, it was found that the certain implemented seagrass was able to significantly reduce wave amplitude. In addition, sensitivity analysis was conducted to evaluate the effect of the changes in several parameters, including the friction coefficient and the length of the seagrass meadow on the wave transmission coefficient. It was found that both parameters are directly proportional to the wave transmission coefficient. In conclusion, the combination of analytical and numerical methods provides a robust understanding of wave attenuation by seagrass. This study contributes to the growing body of knowledge on nature-based solutions for coastal protection, offering practical information for coastal managers and policy makers that seek to improve resilience to wave impacts.