A bromine-containing poly(arylene ether sulfone) was synthesized from a(4-bromo)phenylhydroquinone monomer.A phosphonated derivative was prepared based on above brominated polymer using palladium-catalyst.Aimed at improving the properties for fuel cell applications,a composite membrane was obtained by incorporating sulfonic acid-functionalized polysilsesquioxane into the phosphonated polymer through a sol-gel processing.Both phosphonated membrane and its hybrid membranes show good thermal and dimensio-nal stability.The hybrid membrane has low methanol permeability of 1.07×10-7 cm2/s and proton conducti-vity of 0.06 S/cm at 80 ℃.