Disclosed is an electrode electrolyte for solid polymer fuel cells, which uses a polymer electrolyte containing a polyarylene copolymer containing a nitrogen-containing aromatic ring having a substituent represented by —SO3H, —(O(CH2)hSO3H or —O(CF2)hSO3H (wherein h represents an integer of 1-12). By having such a constitution, the electrode electrolyte for solid polymer fuel cells can be produced at a low cost, while being excellent in proton conductivity, dimensional stability, hydrothermal resistance and mechanical strength. In addition, this electrode electrolyte for solid polymer fuel cells enables to recover a catalyst metal.