The present invention provides a polymer electrolyte material comprising a
polymer having a repeating unit based on an alicyclic fluoromonomer
having a carbon-carbon double bond with radical polymerization
reactivity, wherein either of carbon atoms at both ends of the double
bond constitutes a ring structure; the repeating unit contains a strongly
acidic group such as a sulfonic acid group; the polymer is preferably
perfluorinated. This electrolyte material has a high softening
temperature and a polymer electrolyte fuel cell using this electrolyte
material can be operated at higher temperatures than before. Furthermore,
when this electrolyte material is used for a catalyst layer of a cathode
in a polymer electrolyte fuel cell, an output voltage of the cell can be
increased.