Electro membrane assemblies are formed respectively in openings provided in a substrate. Each membrane electrode assembly is provided with an electrolyte membrane, an anode catalyst layer, and a cathode catalyst layer. A protective layer is provided on the substrate disposed between the adjacent anode catalyst layers. The other protective layer is provided on the substrate disposed between the adjacent cathode catalyst layers. The protective layer and the other protective layer preferably contain a resin whose number of C—F bonds is greater than that of the substrate.