Au nanoparticles/mesoporous CuO nanosheets were successfully synthesized by the assembly of negatively charged AuCl₄⁻¹ and positively charged CuO nanosheets using sodium citrate and thermal reduction, respectively. The structure and morphology were characterized in detail. Both the loading amount of Au nanoparticles and the performance were controlled by the reduction process. The resulting Au/CuO NSs exhibited good catalytic activity for CO oxidation and good non-enzymatic sensitivity for glucose.