Au-core-Pt-shell (Au@Pt) nanoparticles supported on activated carbon (Au@Pt/C) are synthesized by an epitaxial growth method using HCOONa as a reducing agent. Through the characterization of the transmission electron microscope (TEM), high resolution TEM (HRTEM), high angle annular dark-field scanning TEM (HAADF-STEM) and X-ray powder diffraction (XRD), the Pt atoms grow epitaxially on the surface of the Au nanoparticles to form Pt shells with Au fcc structure. According to the results of the X-ray photoelectron spectroscopy (XPS), electrons transfer from Pt to Au. Cyclic voltammetry is employed to investigate the catalytic activities of the Au@Pt/C catalysts for the methanol electrooxidation (MEO) and the CO stripping. The results of the electrochemical measurements indicate that, the Au fcc structure of the Pt shell and the decrease in the electronic effect are propitious to the increases in the catalytic activity for the MEO and the CO tolerance of the Au@Pt/C catalysts. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.