The choice of roll stabilization system is critical for many types of ships. For warships where operational activities are fast and the concept of time is very effective, determining the most appropriate of these systems is of particular importance. Some operations, such as the landing of the helicopter on board, are critical for naval ships. Unwanted rolling motion makes this difficult. In addition, the performance of the crew may be insufficient due to the effect of roll movement. Therefore, the determination of the most effective stabilizing device for naval ships was highly related to the rapid reduction of roll motion. With increasing technological studies, it became important which type of stabilizing system is more suitable for which type of naval ship. This study evaluates the relationship between criteria and alternatives and selects the most effective roll stabilizer system for naval ships according to expert opinion. Extension of TOPSIS method with interval-valued spherical fuzzy sets used to list the stabilizing systems alternatives for naval ships. When the obtained results were evaluated, the effect of the criteria on the alternative system types examined, Active Fin found to be the most functional alternative.