The use of support braced systems represents one of the best solutions for retrofitting or upgrading the tall reinforced concrete buildings in areas with a high earthquake hazard. In this study, the behavior of a reinforced concrete tall structure under seismic loads is examined based on the Turkish Building Earthquake Code 2019 (TBEC-2019). Support braced systems were added to the 25-story structure on 0.4H and 0.8H levels (H is height of structure). For two different models, firstly, the Mode-Superposition Method for linear computational methods used within the scope of strength-based design is performed. In order to determinate more accurately the behavior of tall buildings, as in the earthquake regulations of other developed countries, the TBEC-2019 advises a nonlinear deformation-based design approach. In addition, the nonlinear time history analyses of these buildings were performed. As a result of these analyzes, it was determined whether the two models examined were within the targeted performance effects or not. In the model having support braced system, stiffness and shear forces in shear walls were increased. Thus, displacements, relative story drift, plastic rotations and bending moments of shear walls were decreased.