In this paper, we used a 3D nanoporous carbon (NanoPC) with a high specific surface area of 1037 m(2)/g as a carbon support for high-temperature polymer electrolyte fuel cell, and fabricated an electrocatalyst (NanoPC/PyPBI/Pt) having platinum nanoparticles of ∼2.2 nm diameter deposited on the NanoPC that was wrapped by poly[2,2'-(2,6-pyridine)-5,5'-bibenzimidazole] (PyPBI). Even after 10,000 start-up/shutdown cycles in the range of 1.0 to 1.5 V vs. RHE, the NanoPC/PyPBI/Pt showed almost no loss in electrochemical surface area (ECSA), which indicated much higher durability than those of a CB/PyPBI/Pt (∼32% loss), in which conventional carbon black (CB) was used in place of the NanoPC, and conventional CB/Pt (∼46% loss). The power density of the NanoPC/PyPBI/Pt was 342 mW/cm(2), which was much higher than those of the CB/PyPBI/Pt (183 mW/cm(2)) and CB/Pt (115 mW/cm(2)).