Polybenzimidazole (PBI) was studied as an ionomer binder at varying ratios (1-7) in a 20-40 wt% Pt-Pd/C cathode-coupled catalyst layer for the oxygen reduction reaction (ORR) in a high-temperature proton exchange membrane fuel cell (HT-PEMFC). Catalytic activity was examined by CV and LSV, while the properties of the catalysts were characterized by FESEM-EDX, N-2 adsorption-desorption, XRD and FTIR. The results showed that the distribution of metals on the carbon surface, carbon wall thickness and the interaction between ionomer and coupled catalysts affected the ORR performance. The fabricated membrane electrode assembly with 5:95 PBI: 30 wt% Pt-Pd/C catalyst ratio exhibited the Pt-best performance and highest durability for HT-PEMFC at 170 degrees C, yielding a power density of 1.30 Wcm(-2) with 0.02 mg(P)(t)/cm Pt loading. This performance of ultra-low metal loading of coupled Pt-Pd/C electrocatalyst with PBI binder was comparable to those reported by other studies, highlighting a promising catalyst for fuel cell application. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.