Two VOx/SBA-15 catalysts and three VOx/SiO2-fumed silica, with 5, 10 and 1, 5, 10 %wt. vanadium content respectively, were tested in a stainless steel continuous flow reactor for the partial oxidation of ethanol. The catalysts were tested at 150 – 300 °C. Products were analyzed by GC-FID, GC-OFID and GC-MS. The aim was exploring the problematics which could be found when more industrial close conditions are used. The total conversion of ethanol and selectivity to acetaldehyde were different than the expected ones. For VOx/SiO2-fumed silica, the total conversion was higher with a lower selectivity to acetaldehyde compared to VOx/SBA-15 catalysts.