The performances of the proton exchange membrane fuel cell (PEMFC), direct formic acid fuel cell (DFAFC) and direct methanol fuel cell (DMFC) with sulfonated poly(ether sulfone) membrane are reported. Pt/C was coated on the membrane directly to fabricate a MEA for PEMFC operation. A single cell test was carried out using H-2/air as the fuel and oxidant. A current density of 730 mA cm(-2) at 0.60V was obtained at 70 degrees C. Pt-Ru (anode) and Pt (cathode) were coated on the membrane for DMFC operations. It produced 83 mW cm(-2) maximum power density. The sulfonated poly(ether sulfone) membrane was also used for DFAFC operation under several different conditions. It showed good cell performances for several different kinds of polymer electrolyte fuel cell applications.