Effects of a Cu-based catalyst on the catalytic performance in alcohol-hydrocarbon synthesis from syngas have been investigated, using various supports. Under the different porosities of three supports (zinc oxide, activation carbon, and titanium dioxide), whereas Cu/ZnO produces one liquid phase of major mixed alcohols, Cu/AC and Cu/TiO2 create two phases, alcohol(~75%) and hydrocarbon (~25%). X-ray diffraction shows that CuO impregnated on supports undergoes a complete reduction of metallic copper Cu0, which is the real active phase in the catalytic process. The Cu/TiO2 catalyst showed the highest ethanol composition in a mixed alcohol phase under GHSV 18,000 h^(-1), 30 bar, and 300 ℃.