The gas-solid photocatalytic partial oxidation of ethanol to acetaldehyde on monometallic RuOx/TiO2 and bimetallic RuOx-VOx/TiO2 catalysts has been studied in a fluidized bed photoreactor at high illumination efficiency. For RuOx/TiO2, by increasing ruthenium loading ethanol conversion decreased from 60 to 37 %, while acetaldehyde selectivity increased to about 97 % at 0.4 wt % RuO2 loading. With bimetallic RuOxVOx/TiO2 the selective yield to acetaldehyde by monometallic Ru based catalysts is enhanced by the highly active V species, resulting in higher photocatalytic performance. By increasing the vanadium loading, ethanol conversion increased up to 100 % with almost total selectivity to acetaldehyde.