In the low-temperature water-gas shift reaction, the effect of the catalyst pretreatment conditions on the adsorption state of CO was investigated on a structured copper-based catalyst, which was prepared by electroless plating. The amount of CO adsorbed on the catalyst was higher due to the oxidation pretreatment than that by the reduction treatment. The CO adsorbed on the oxidized catalyst formed many carbonate and carboxylate species, which have a slightly weak adsorption. Such an adsorption state would enhance shift performance.