A novel MEA is fabricated to improve the performance of air-breathing direct methanol fuel cells. A diffusion barrier on the anode side is designed to control methanol transport to the anode catalyst layer and thus suppressing the methanol crossover. A catalyst coated membrane with a hydrophobic gas diffusion layer on the cathode side is employed to improve the oxygen mass transport. It is observed that the maximum power density of the advanced DMFC with 2 M methanol solution achieves 65 mW cm(-2) at 60 degrees C. The value is nearly two times more than that of a commercial MEA. At 40 degrees C, the power densities operating with 1 and 2 M methanol solutions are over 20 MW cm(-2) with a cell potential at 0.3 V. (c) 2006 Elsevier B.V. All rights reserved.