The mixed alcohols were synthesized at different reaction temperatures, different GHSVs, and different pressures over K-MoO3 supported on different supports such as gamma-Al2O3 and SiO2. The ammonia adsorption over the catalysts was studied using temperature program desorption (TPD). The ethanol decomposition was studied over these catalysts, which has shown that the decomposition activity was higher for the catalyst calcined at 500 degrees C than for the catalyst calcined at 800 degrees C. However, the activity for ethanol decomposition was low over a K-Mo-unsupported sample. The activity and selectivity of the catalysts increased in the order of K-MoO3/gamma-Al2O3 < K-MoO3/SiO2 < unsupported K-Mo. If the oxidized supported catalysts were recalcined at 800 degrees C, the yields of CO2 and hydrocarbons were suppressed and the yields of mixed alcohols were remarkably enhanced. However, the unsupported K-Mo has not shown any effect.