Energy-efficient CH4-CO2 valorization to fuels and chemicals presents an urgent need considering the great variety of methane sources and the removal of greenhouse gases. In the present work, the microwave-assisted dry reforming of methane, DRM, has been carried out in a custom-designed rectangular mono-mode microwave applicator over several catalyst-support combinations, i.e., Pt/C, Ni/Al2O3, mechanical mixture of Ni/Al2O3-SiC and Ni/SiC. The high and steady conversions of CH4 and CO2 were obtained in the case of the mechanical mixture of Ni/Al2O3-SiC and Ni/SiC. In all the combinations investigated, the conversions reached up to 90% at a WHSV of 11,000 mL/g/h, and microwave power input of 45–60 W, at 800 °C. No significant catalyst deactivation has been observed during the 6-h operation except of Pt/C catalyst. Moreover, the microwave-assisted dry reforming of methane over Ni/SiC was shown to be an interesting, cheap process candidate, able to compete with the steam reforming.