NOVELTY - Manufacturing a membrane electrode assembly (8) including catalyst layers (2, 3) formed on both sides of a polymer electrolyte membrane (1), involves forming a first layer including catalyst or catalyst precursor on a surface of a sheet by vapor-phase deposition; forming a through hole in the first layer; forming a second layer including catalyst or catalyst precursor on a surface of the first layer having the through hole by vapor-phase deposition; joining a polymer electrolyte membrane to a surface of the second layer; and peeling off the sheet from the first layer.    USE - For manufacturing a membrane electrode assembly for fuel cell (claimed), useful in automobiles, household power generators, and portable electrical apparatuses such as mobile phones, notebook personal computers and digital cameras.    ADVANTAGE - The substance diffusion of the obtained membrane electrode assembly is improved, and an output reduction of the fuel cell caused by flooding of the catalyst layer is suppressed, thus a fuel cell stably driving for a long time can be obtained. The method provides a membrane electrode assembly excellent in substance diffusion and catalyst use efficiency. Because catalyst use efficiency can be improved, a catalyst amount to be used can be reduced, thus reducing costs of the membrane electrode assembly and the fuel cell. In the membrane electrode assembly and the fuel cell, substance diffusion and catalyst use efficiency are improved. The fuel cell including membrane electrode assembly, has high-output and stable power generation characteristics.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) manufacturing a fuel cell involving manufacturing a membrane electrode assembly; and forming gas diffusion layers (4, 5) on both sides of the membrane electrode assembly;    (2) a membrane electrode assembly comprising catalyst layers formed on both sides of a polymer electrolyte membrane, at least one of which has a dendritic shape, where each catalyst layer having the dendritic shape includes a macrocrack and a through hole, and an opening ratio of the through hole in an area surrounded with the macrocrack of the catalyst layer having the dendritic shape in a surface opposed to the polymer electrolyte membrane is 8-40%.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of single unit sectional configuration of a polymer electrolyte fuel cell.    Polymeric electrolyte membrane (1)    Anode side catalyst layer (2)    Cathode side catalyst layer (3)    Anode side gas diffusion layer (4)    Cathode side gas diffusion layer (5)    Anode side electrode (6)    Membrane electrode assembly (8)    Gas diffusion (10)