The needs of Indonesian people for places to live and work keeps increasing along with the improvement of its population growth. Unfortunately, the areas for developing buildings get decreasing. One of solution for overcoming this problem is by conducting vertical development such as building an apartment. Many apartments with various innovations have been developed by developers to attract consumers such as the existence of swimming pool on the top of building. However, this sort of vertical development plan is very prone to earthquake as Indonesia has high potential of it. This research analyzed the structural behavior of buildings with and without swimming pool. In addition, it analyzed the need of reinforcement for apartment building structure with swimming pool on the top of building toward the seismic load based on SNI 1726:2019. The analysis of seismic load employed spectrum response method. Meanwhile, the need of reinforcement was analyzed based on the plan of dual system by combining Special Moment Resisting Frame System and Special Structural Wall System. The control upon the structural behavior involved the provision of greater drift and period of building structure with swimming pool than without it. The results of research demonstrated that the need of reinforcement for both floor plate thicknesses was Ø10-100. The needs of beam reinforcement in the dimension 350/500 were 5D19 for pedestal area and 3D19 for ground area. Besides, column 750/750 required reinforcement 28D32, whereas the area of beam-column connections necessitated reinforcement 3 feet Ø16-100. The shear wall in 350 mm thick needed 2 rows reinforcement of 28D36. The wall of swimming pool planned in 150 mm thick required reinforcement Ø10-100. Furthermore, the plate for swimming pool base in 200 mm thick demanded reinforcement of Ø10-50 for pedestal area and Ø10-100 for ground area.