Structural monitoring of prestressed concrete sleepers is essential to ensure the safety and durability of railway systems, especially under severe operating conditions. In this context, modal analysis becomes a valuable tool for identifying changes in the dynamic properties of sleepers, allowing early detection of structural degradation. With this in mind, this study presents the modal analysis of prestressed concrete sleepers used in metric gauge railway systems to evaluate the changes in modal properties under different levels of damage caused by the progressive loading at midspan, providing information on the structural performance of the sleepers. The experimental test was carried out using five accelerometers strategically positioned along the sleeper, and the input excitation was applied using an instrumented impact hammer. The modal test was carried out for the intact sleeper and immediately after applying 4 different load levels. The natural frequencies, damping, and vibration modes were extracted using MATLAB, which processed the Frequency Response Functions (FRFs) from the recorded data. As a result, the damping ratio showed greater sensitivity to the damage inputs compared to the natural frequencies. Additionally, the mode that was the most sensitive to this damage by flexural load application was the first flexural mode.