A sequential design and global optimization method is proposed to coordinately design local and widearea controllers to enhance the overall stability of largescale power system. The sequential design is used to assign the distributed local power system stabilizer (LPSS) and high-voltage direct current (HVDC) wide-area stabilizing controller (HVDC-WASC) to the concerned damping modes. The global optimization is used to simultaneously optimize all the overall control gains of LPSSs and HVDCWASC. Moreover, the optimization model, which has an adaptive ability of searching and updating dominant oscillation modes, is established. Both the linear analysis and nonlinear simulation results verify the effectiveness of the proposed design method in enhancing the stability of large-scale power systems.