MEMBRANE ELECTRODE ASSEMBLY, AND POLYMER ELECTROLYTE FUEL CELL

A membrane electrode assembly includes: a polymer electrolyte membrane having a first surface and a second surface facing away from the first surface; an anode-side electrode catalyst layer bonded to the first surface; and a cathode-side electrode catalyst layer bonded to the second surface. The cathode-side electrode catalyst layer and the anode-side electrode catalyst layer each contain a catalyst material, a conductive carrier that supports the catalyst material, a polymer electrolyte, and a fibrous material. The thickness of the anode-side electrode catalyst layer is greater than the thickness of the cathode-side electrode catalyst layer.