The present study investigated the influence of preparation conditions of hollow spheres of copper-cerium composite oxide on the morphology and catalytic activity for oxidation of carbon monoxide. The hollow spheres were obtained by a hydrothermal method using silica templates, and the homogeneity of the hollow spheres depended on the amount of urea used during preparation. X-ray diffraction studies indicated that the dispersion of CeO2 in the copper-cerium composite oxide increased with the addition of urea during preparation. In addition, X-ray photoelectron spectroscopy studies indicated that the amount of surface copper also increased with the addition of urea. The hollow spheres prepared with urea showed a higher catalytic activity for oxidation of carbon monoxide than the sample prepared without urea due to the morphological homogeneity, dispersion of CeO2, and surface composition of Cu species.