The catalytic reduction of CO2 by the reverse water gas shift (RWGS) reaction at atmospheric pressure has been investigated over different molybdenum carbides supported on gallium doped ZnO-ZrO2(ZZG) materials. The catalysts have been characterized by nitrogen adsorption-desorption isotherms and using diverse techniques such as powder X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and X-ray photoelectron (XPS) and Raman spectroscopy. MoC, Mo2C and MoxC (containing MoC and Mo2C) have been incorporated to the supports by using an ultrasound-assisted method. The catalytic behavior of the prepared materials in the RWGS reaction was analyzed using a H2/CO2=3 mixture in the 250-450 ºC range. The new catalysts were active for the CO2 reduction to CO. The supported catalyst MoxC/ZZG, containing both MoC and Mo2C, resulted in improved yield of CO in the overall range of temperature. All supported catalysts showed high stability under the reaction conditions used.