In this paper, the plasma coupled catalyst was used for the dry reforming of methane (DRM). The impacts of the reaction temperature, the molar ratio of CO2/CH4, and the concentration of the main gas components (N2, H2, CO, H2O) on the conversion rate of CH4 and the energy efficiency of plasma catalysis were observed. The results shows that the conversion rate of CH4 is 41.57%, with La-Ni/γ-Al2O3 as the catalyst, the reaction temperature being 450°C and the molar ratio of CO2/CH4 being 1.0, and without other gases. The conversion rate of CH4 increases with the increase of the molar ratio of CO2/CH4. The conversion rate of CH4 is 92.82% respectively during DRM by plasma catalysis, with the molar ratio of CO2/CH4 being 5.0. The reaction temperature and the molar ratio of CO2/CH4 have a significant effect on CH4 conversion. The excited particles in the system are influenced by the changes of gas composition, which affect not only CH4 conversion directly, but also the carbon deposition on the surface of catalyst. The addition of N2 and H2O in the reaction system not only improves conversion of CH4 but also inhibits carbon deposition; the addition of H2 and CO reduces the conversion of CH4 significantly. The results are expected to provide basic data and reference for the development of the synthetic process of chemicals through biomass gasification.