Tin oxide (SnO2)/graphene nanosheets (GNS) composite was prepared by a simple chemical-solution method as the catalyst support for direct ethanol fuel cells. Then the SnO2-GNS composites supporting Pd (Pd/SnO2-GNS) catalysts were synthesized by a microwave-assisted reduction process. The Pd/SnO2-GNS catalysts were characterized by using X-ray diffraction, transmission electron microscopy and energy-dispersive spectroscopy techniques. The electrocatalytic performances of Pd/SnO2-GNS catalysts for ethanol oxidation were studied by cyclic voltammetric and chronoamperometric measurements. It was found that compared with Pd/GNS, the Pd/SnO2-GNS catalyst showed superior electrocatalytic activity for ethanol oxidation when the mass ratio of SnCl2·2H2O precursor salt to graphite oxide was about 1:2.