A series of poly(arylene ether ketone)s carrying 3-methoxyphenyl side group from 3-methoxy-phenylhydroquinone and difluoro monomers via copolymerization reaction were prepared.Then those polymers were sulfonated by stirring in concentrated sulfuric acid at room temperature.The structure and property of the polymers were characterized and studied.All of the polymers were easity cast into tough membrance.The obtained sulfonated polymers exhibited a good thermal stability,a high proton conductivity(>0.90 S/cm at 80 ℃)and excellent mechanical properties.