A power generating apparatus includes a proton conductor unit, containing a fullerene derivative, a hydrogen electrode bonded to one surface of the proton conductor unit, an oxygen electrode bonded to the other surface of the proton conductor unit, and a hydrogen gas supplying unit for supplying a hydrogen gas at a pressure of approximately 0.2 to approximately 3.5 atm to the hydrogen electrode. The present power generating apparatus effectively suppresses transmission of hydrogen and oxygen gases so that it is possible to prevent the hydrogen gas from being emitted to atmosphere due to transmission as well as to prevent the oxygen gas from reaching the hydrogen electrode on transmission to prevent the hydrogen gas from being consumed without contributing to power generation.