This study analyzes how modified flow field affects non-isothermal transport characteristics and cell performance of the proton exchange membrane fuel cell (PEMFC) by the finite-volume SIMPLE-C method coupled with preconditioned conjugate gradient methods. The modified flow field is obtained by rectangular obstacles opposite or staggered with the protuberant catalyst layer surface or narrowed flow channel, with ribs opposite or staggered with the protuberant catalyst layer surface. This study also considered the effect of liquid water formation on the fluid flow field. The cell performance of the modified flow field is compared with that of the conventional flow channel. The comparison result demonstrates that the narrowed flow channel with ribs opposite the protuberant catalyst layer surface has the best increase rate in cell performance. The increase rate is approximately 8%. (C) 2013 ElsevierLtd. All rights reserved.