Although Double Concave Friction Pendulum (DCFP) bearings have been ‎widely investigated for seismic isolation of buildings, existing design ‎approaches mainly rely on predefined bearing configurations or isolated ‎optimization of individual parameters, while coordinated optimization of ‎geometric and frictional characteristics for tall buildings remains limited. ‎This study proposes an Optimized Double Concave Friction Pendulum (O-‎DCFP) through simultaneous optimization of sliding-surface curvature radii ‎and friction coefficients using an integrated Design of Experiments (DOE)–‎Response Surface Methodology (RSM) framework. Four design variables (R₁, ‎R₂, μ₁, and μ₂) were investigated using an 18-run I-optimal design. Each ‎configuration was evaluated by nonlinear response-history analyses of a 60-‎story steel benchmark building under eleven spectrum-compatible far-field ‎earthquake records, resulting in 198 nonlinear dynamic simulations. ‎Response surface models predicted four key response parameters: effective ‎structural period, structural plastic energy, maximum interstory drift ratio, ‎and peak floor acceleration. Desirability-based multi-objective optimization ‎identified the optimum O-DCFP configuration (R₁ = 610 mm, R₂ = 1000 mm, ‎μ₁ = 0.08, and μ₂ = 0.16), reducing the effective structural period by 4.0%, ‎mean structural plastic energy by 5.4%, maximum interstory drift ratio by ‎‎20.3%, and mean peak floor acceleration by 14.3% compared with a ‎conventional DCFP configuration. Independent nonlinear verification ‎analyses confirmed prediction errors below 4%, while application to 40- and ‎‎90-story buildings demonstrated consistent improvements without ‎recalibration, confirming transferability. The proposed DOE–RSM ‎framework provides an efficient methodology for performance-based ‎optimization of friction pendulum isolation systems with substantially lower ‎computational cost, demonstrating that coordinated optimization of sliding-‎surface geometry and frictional characteristics improves seismic ‎performance without relying solely on increasing the isolation period.‎