Proton–conducting polymer membranes are used as an electrolyte in the so - called proton exchange membrane fuel cells. Current commercially available membranes are perfluosulfonic acid polymers, a class of high –cost ionomers. This paper examines the potential of polymer blends, namely those of sulfonated poly styrene ethylene butylene poly styrene (SPSEBS) and poly styrene ethylene butylene poly styrene (PSEBS), in the proton exchange membrane application. SPSEBS / PSEBS blends were prepared by solvent evaporation method. SPSEBS membranes exhibited good conductivity, flexibility and chemical stability while they had poor mechanical stability. In an effort to improve the mechanical properties of SPSEBS while maintaining the initial conductivity, it was incorporated with PSEBS. The obtained membranes were characterized in terms of conductivity, ionic exchange capacity and water uptake. Blend membranes were studied by FTIR spectroscopy and X-ray diffraction. The morphology of the membranes was studied by scanning electron microscope (SEM). Thermal stability of the membranes was studied by TGA and DSC. Fuel cell performance studied by PEMFC and DMFC.