Abstract: The composite support (PAnC) with conductive polymer polyaniline and activated carbon are prepared. The catalytic performance of the Pd catalyst prepared with PAnC as a support is better than that of the catalyst prepared with activated carbon alone. In addition, the polyaniline carbon support (PAnC-S), which prepared with doping sodium dodecyl sulfate, owns lower charge transfer resistance, more mesoporous between 10~25 nm, larger specific surface area, 94.9 m²/g. PAnC-S and PAnC have uniform particle sizes of about 30 nm. The Pd catalysts prepared with PAnC-S and PAnC support have larger electrochemical surface area, 84.7 and 62.6 m²/g, respectively. Pd/PAnC-S and Pd/PAnC have higher activity and stability for formic acid electrooxidation compared with the Pd/C.