Using Ce(NO3)3·6H2O, Cu(NO3)2·3H2O, and SnCl4·5H2O as raw materials, and NaOH as the precipitant, CuSnCe⁃C, CuSnCe⁃PI, and CuSnCe⁃CH catalysts were prepared by co⁃precipitation, precipitation⁃impregnation, and co⁃precipitation⁃hydrothermal methods, respectively. The catalysts were characterized using characterization techniques such as XRD, BET, H2⁃TPR, and XPS, and their CO preferential oxidation performance was evaluated under a hydrogen⁃rich atmosphere. The results show that changes in preparation methods significantly affect the physical and chemical properties as well as the catalytic performance of the catalysts. Among them, the CuSnCe⁃CH catalyst prepared by the co⁃precipitation⁃hydrothermal method exhibits the best catalytic performance. Under atmospheric pressure, at a reaction temperature of 140 ℃, an oxygen excess factor of 2.6, and a mass space velocity of 20 244 mL/(g·h), the CO conversion rate reaches a maximum of 94.9%, with a CO oxidation selectivity of 43.2%. Consistent with the characterization results,catalysts with smaller average grain size, larger specific surface area, higher CuO dispersion, lower reduction temperature, and higher oxygen vacancy content exhibit the best CO preferential oxidation performance.