Proton exchange membranes based on fluorinated poly（ether sulfone）s with disulfonated naphthyl pendants （sSPFES） have been successfully prepared by post functionalization through polymeric SNAr reaction. Copolymer structure was confirmed by H-nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy, the physico-chemical properties of the sSPFES membranes were evaluated by thermogravimetric analysis, gel permeation chromatography, electro-chemical impedance spectroscopy, atomic force microscopy, Fenton, water-swelling and fuel cell test. The pendant grafting degree was controlled by varying the feeding amount of the disulfonaphthols, resulting in the ion exchange capacity about 1.28-1.73 mmollg. The obtained sSPFES membranes were thermal stable, mechanical ductile, and exhibited dimensional change less than 17%, water uptake below 70%, and proton conductivity as high as 0.17-0.28 S/cm at 90℃ in water. In a single H2/O2 fuel cell test at 80℃, the sSPFESB-3.2 membrane （1.61 mmol/g） showed the maximum power output of 593-658 mW/cm^2 at 60%-80% relative humidity, indicating their rather promising potential for fuel cell applications.
