The highly effective catalytic conversion of CO2 into valuable compounds was investigated by multi-functional catalysts composed of base-metal oxides as the main components promoted by a low concentration of precious metals and gallium oxide. The desired reduced state of catalyst metal oxides for exhibiting the optimum catalytic performance could be controlled by both the hydrogen spillover on the precious metal parts and the inverse-spillover from the Ga parts. By applying those principal concepts in the catalyst structure-design, the rapid CO2 reforming of methane, the rapid CO2 methanation, the effective synthesis of methanol and/or ethanol from CO2 and H-2, and selective syntheses of high quality gasoline and/or light olefins by means of one-pass conversion of CO2-H-2 mixture via methanol as the intermediate product, were respectively realized. Those novel catalytic reactions would have a high potential to moderate the accumulation of CO2 come from fossil fuel combustion, while compensating the cost of hydrogen as the reducing reagent.