A polymer electrolytic material has excellent proton conductivity and
excellent fuel shutting property, and accordingly provide a polymer
electrolytic fuel cell with a high efficiency. This polymer electrolytic
material has an unfreezable water ratio Rw1 defined by the following
expression (S1) in a range of 20 to 100% by weight in hydrated state:
Rw1=[Wnf/Wfc+Wnf)].times.100 (S1) in which Wnf represents the
unfreezable water content per 1 g of the polymer electrolytic material in
dry state and Wfc represents the low freezing point water content per 1 g
of the polymer electrolytic material in dry state.