In order to achieve the highly-effective gas-phase selective oxidation of alcohols, the gold catalyst was prepared using Mn3O4-modified SiO2 as support, and the modification conditions of support, the preparation and reaction conditions of catalyst were investigated. The results showed that benzyl alcohol conversion and benzaldehyde selectivity were enhanced over the modified catalyst. For example, benzyl alcohol conversion of 96% and benzaldehyde selectivity of 98% could be achieved at 250℃. The catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM), and the results showed that the Mn3O4 was dispersed in the form of monolayer. Gold particle size is 12-14 nm, but exhibits excellent performance for the alcohol oxidation due to the Au-Mn3O4 interaction.