Composite microparticles consisting of large gold (Au) particles embedded with multi-walled carbon nanotubes (MWCNTs), denoted as MWCNTs-Au, have been successfully prepared by a facile hydrothermal process of gold(III) chloride (AuCl3) in a MWCNT aqueous solution. X-ray diffraction and scanning electron microscopy reveal that the obtained Au particles have an average diameter of about 500 nm and some MWCNTs are inserted into the Au particles. The MWCNTs-Au composites in the ethanol oxidation reaction (EOR) show quite different shape of cyclic voltammograms (CVs) toward EOR when compared to the previous CV reports on the pure Au substrate.