NOVELTY - Membrane electrode assembly includes catalyst layers for fuel and oxidants having electrically conductive and electrolyte materials, in which the electrolyte materials of the catalyst layers for fuel and for oxidants have a larger amount per unit weight of respective hydrocarbon electrolyte and fluorocarbon electrolyte than that the catalyst layer for oxidants and for fuel.    USE - For use in proton exchange membrane fuel cell (claimed).    ADVANTAGE - The inventive membrane electrode assembly and the proton exchange membrane fuel cell result in low costs and produce both a satisfactory level of output voltage and durability.    DETAILED DESCRIPTION - Membrane electrode assembly (1) sequentially comprises:    (A) gas diffusion layer for fuel (3) to which fuel is supplied;    (B) catalyst layer for fuel;    (C) electrically conductive material and an electrolyte material;    (D) electrolyte membrane (4) having ionic conductivity;    (E) catalyst layer for oxidants (5, 6) and having an electrically conductive material and an electrolyte material; and    (F) gas diffusion layer for oxidants to which oxidizer gas is supplied.    The electrolyte material of the catalyst layer for fuel includes a larger amount per unit weight of a hydrocarbon electrolyte than that in the electrolyte material of the catalyst layer for oxidants. The electrolyte material of the catalyst layer for oxidants includes a larger amount per unit weight of a fluorocarbon electrolyte than that in the electrolyte material of the catalyst layer for fuel. An INDEPENDENT CLAIM is also included for a proton exchange membrane fuel cell sequentially comprising a fuel distribution plate to which fuel is supplied, the membrane electrode assembly, an oxidant distribution plate for supplying oxidizer gas to the gas diffusion layer for oxidants.    DESCRIPTION OF DRAWING(S) - The figure illustrates a cross section that indicates a conceptual image in which a fuel distribution plate and an oxidizer gas distribution plate are positioned at the membrane electrode assembly.    Membrane electrode assembly (1)    Fuel (3)    Electrolyte membrane (4)    Oxidants (5, 6)