Hydrogen was electrochemically compressed using the membrane electrode assembly (MEA) film of hydrogensulfated fullerenol [C-60(OSO3H)(n)(OH)(n)]. The material works as proton conductor without further humidification at ambient temperature. Hydrogen was compressed up to 1 MPa using one MEA. The amount of compressed hydrogen and the potential to compress hydrogen follow the Faraday's law and Nernst equation. We confirmed the storage of the electrochemically compressed hydrogen in an AB(5)-type alloy. (C) 2002 The Electrochemical Society.