After the deposition of Pt on their surface, the carbon nanofiber materials synthesized by sequential oxidation and pyrolysis of electrospun nanofiber mats based on polyacrylonitrile are used as the gas-diffusion electrodes for high-temperature hydrogen-air fuel cells on a polybenzimidazole (PBI) proton-conducting membranes. In contrast to the traditional methods of electrode preparation in which the catalyst (Pt) nanoparticles are localized on the surface of carbon black which is applied as "ink" on the conducting support (carbon paper or tissue), in this study the Pt nanoparticles are being deposited and developed on the surface carbon nanofibers to form a combined gas-diffusion material. In the tests, the resulting electrodes demonstrate good efficiency within hydrogen-air fuel cells on the PBI membrane.