Bimetallic Cu@Au core/shell nanoparticles were prepared by the wet chemical reduction method using Tween as the organic modifier. The Cu@Au nanoparticles exhibited higher catalytic activity for the oxidation of 1,2-propanediol under mild reaction conditions than the sole Au nanoparticles. The Cu@Au nanoparticles with the mole ratios of Au to Cu of 0.015:0.985 and 0.035:0.965 exhibited high catalytic activities for the catalytic oxidation of 1,2-propanediol to lactic acid. A power function type reaction kinetic model well fitted the experimental data over the Cu0.985Au0.015 nanoparticle catalyst, r = -dn (0) /(dt center dot W (cat) ) = kC (0) (0.49) P (0) (0.39) , and the reaction activation energy was 34.1 kJ mol(-1).