The present invention relates to a laminated membrane comprising a
membrane (I) which comprises aromatic polymer electrolyte containing a
super strong acid group and a membrane (II) which comprises one compound
selected from the group consisting of electrolytes of
perfluoroalkylsulfonic acid polymer and non-super strong acid polymer,
and a laminated membrane comprising a membrane (III) which comprises a
perfluoroalkylsulfonic acid polymer electrolyte and a membrane (IV) which
comprises a non-super strong acid polymer electrolyte. The laminated
membrane of the present invention is an electrolyte membrane excellent in
generation performance and excellent also in the respect of mechanical
strength.