Cobalt-free perovskite oxides with mixed ionic and electronic conducting (MIEC) properties have been considered as promising alternatives for solid oxide fuel cell (SOFC) cathode material. Among the cobalt-free perovskite oxides, iron-based perovskite oxides have received much spotlight as potential candidates for high-temperature SOFC cathode material attributed to their great catalytic activity for the oxygen reduction reaction (ORR) and excellent cell operation durability. Herein, Sr-doped Pr0.5Ba0.4Sr0.1FeO3-delta (PBSF) is presented with the aims of enhancing the catalytic activity for ORR while retaining great durability for yttria-stabilized zirconia (YSZ)-supported SOFC. The developed PBSF exhibited outstanding cathodic polarization resistance of 0.05 omega cm(2) at 850 degrees C, which is 3 times lower than the commercial La1-xSrxMnO3-delta. Furthermore, there is no observable degradation for 50 hours. This study presents a great potential to replace the commercial cathodes for YSZ-supported SOFC.