Organic-inorganic hybrid polymers based on poly(arylene ether sulfone) (PAES) containing mult-isulfonated polyhedral oligosilsesquioxane (POSS) pendants (PAES-sPOSS-x) were synthesized to improve the inorganic fillers' distribution in polymer matrix and to enhance the ion conductivity and swelling resistance of aromatic polymer electrolyte membrane. The synthesis of the graft hybrid polymers in this study involves the grafting of mono-functional 3-Iodopropylheptaphenyl POSS with an -OH functionalized polymer main-chain and postsulfonation of the POSS grafted PAES. Notably, nearly all of the benzene rings on the POSS side chains were sulfonated successfully without any sulfonation of main chains. The structure with hydrophobic aromatic backbone and hydrophilic hybrid side chains made an improvement of the nano-phase hydrophilic/hydrophobic separation, thereby facilitating the formation of continuous proton exchange channels. The transmission electron microscopy (TEM) images of the comb-shaped polymer membranes showed homogeneous sulfonated POSS (sPOSS) dispersion, significant phase separation and well-defined interconnected hydrophilic networks. This morphological structure leaded to dramatically enhanced comprehensive properties as proton conductive membranes. (C) 2017 Elsevier Ltd. All rights reserved.