Porous conducting carbon paper has been identified as one of the most suitable materials to be used as an electrode support in a polymer electrolyte membrane fuel cell (PEMFC). Carbon paper was prepared following a combined technique of papermaking followed by composite formation. Samples were prepared with varying thickness while maintaining a uniform composition and a constant density of 0.50 g/cc. The effect of the thickness on various properties of carbon paper affecting its performance in the PEM fuel cell and cell efficiency has been discussed. Power density as high as 805 mW/cm(2) has been achieved for PEM fuel cell employing carbon paper sample with 0.028 cm thickness, an increase of more than 55% as compared to 510 mW/cm(2) for 0.046 cm thick sample.