Abstract: Buckling-restrained brace ( BRB) is introduced in the reinforced concrete frame-bent structure in order to provide a new solution to large thermal power plants in seismic region of intensity 8． Based on an actual project，a sample design of BRB-frame-bent system was developed considering site condition 2 with seismic intensity 8． Two finite element models with and without BRBs were established with nonlinear analytical software Perform 3D and elasto-plastic time history analyses under rare earthquakes were performed． Analytical results showed that BRBs dissipated a large amount of seismic energy，which would otherwise mostly suffered by columns，and thus the damage to bottom weak floor could be avoided，ensuring the safety of the structure under rare earthquakes and qualifying a superior seismic resistant structural system．