The influence of the crystal structure of TiO2 Support material on Pd catalyst-mediated formic acid electrooxidation was investigated. Pd/TiO2 catalysts were synthesized by loading Pd on TiO2 with different crystal structures obtained by calcinations at different temperatures. Electrochemical tests showed that TiO2 with the rutile structure improved the catalytic activity of Pd nanoparticles toward formic acid electrooxidation. Physicochemical and electrochemical characterizations revealed that the enhancement of Pd/TiO2 (rutile) catalytic activity arose from uniform dispersion of Pd nanoparticles, an increase in surface-active sites, and good tolerance to the adsorption of poisonous intermediates (such as COad, COOHad and so on). (C) 2009 Published by Elsevier Ltd.