The electrocatalytic oxidation of glucose in an alkaline solution was examined using gold and gold-platinum alloy nanoparticles as catalysts. In electrolysis, the catalytic activity for oxidation of glucose could be kept much longer time at gold nanoparticle-modified electrode than at a gold plate electrode. Preliminary electrolysis results at 0.3 V indicated that current efficiency for oxalate as 18-electron oxidation product at gold nanoparticle-modified electrode was approximately twice higher than that at gold-platinum alloy nanoparticle-modified electrode.