Effect of CO2 on the reaction performance of the partial oxidation of methane over a LiLaNiO/gamma-Al2O3 catalyst was investigated with a fixed-bed flow microreactor, XRD and UVRRS, etc. By adding CO2 to the partial oxidation of methane, CH4 and CO2 conversions change slightly, while the H-2/CO ratio obviously alters. When combining the exothermic partial oxidation reaction with the endothermic carbon dioxide reforming process, the catalyst bed temperature profiles vary considerably, and the temperature of the hot spots in the catalyst bed reduce significantly, compared with that of the partial oxidation of methane. The 100h Life-test results indicate that the LiLaNiO/gamma-Al2O3 catalyst has good thermal stability, stable crystal phase and excellent carbon deposition resistance during the natural gas-CO2-O-2 reaction at 850 degrees C.