Abstract: Pt/N-CeO₂-X catalyst was prepared by hydrothermal method and thermal polycondensation method, and its catalytic performance on methanol steam reforming reaction was investigated. The effect of nitrogen doping on the reforming performance and the catalytic mechanism were investigated. The results of XRD and FT-IR show that N-doping enhances the characteristic peak strength and widens the functiona crystal. The SEM results show that the catalyst was rod-like structure with a length of 64-67 nm and a diameter of 6-7 nm. The BET and CV curves show that the specific surface area of N-doped catalyst is 111.904 m²/g, which is 2.3 times higher than that of Pt/CeO_2, and the Cdl value is increased to 41.12 μF·cm⁻². Raman tests show that the oxygen vacancy concentration of Pt/N-CeO₂-2 is 9.29%, while that of Pt/CeO₂ is only 3.32%. The lattice oxygen intensity of Pt/N-CeO₂-2 is higher than that of Pt/CeO₂. The results of methanol steam reforming cycle test show that the average H₂ generation rate is 12.5 mmol/h·g after reaction for 40 h, and the catalyst has good reaction stability. The result of kinetic analysis show that the apparent activation energy of Pt/N-CeO₂-2 was 66.36 kJ/mol, indicating that the energy barrier needed to be overcome was the lowest and the thermochemical reaction path was the best. Above results indicate that the pretreatment of the substrate by doping elements can improve the interface interaction between the metal and the substrate, and then adjust the strength of the metal-oxygen bond, so that the surface of the substrate is exposed to more lattice oxygen, which is conducive to the catalytic effect of methanol steam reforming.