In this study, we investigate the potential relationship between the occurrence of resonance phenomena and trapezoidal breakwaters. Specifically, we aim to determine whether resonance is consistently generated by trapezoidal breakwaters. The model is solved analytically using the Shallow Water Equations to determine the natural wave period, which corresponds to the period of the incoming water wave that may trigger resonance. To gain deeper insights into this resonance phenomenon, we conduct numerical simulations using the Finite Volume Method on a Staggered Grid to simulate the wave height at the basin’s edge over time. Several distinct cases are examined to verify whether resonance phenomena will always occur under these conditions. This research is expected to provide valuable new insights, particularly concerning the application of trapezoidal breakwaters in coastal protection.