Silicon oxidation by the aerial diffusion of active oxygen species from a UV-irradiated TiO2 surface was evaluated and characterized. The key point was to confirm the oxidation possibility of inorganic materials such as silicon under a photocatalytic remote scheme. In this study, it was confirmed that the remote oxidation of silicon substrates would occur by the aerial diffusion of active oxygen species from UV-irradiated TiO2 surfaces, and that the oxides have comparable properties to the thermally grown oxide. Remote oxidation using UV-irradiated TiO2 is shown to be a viable alternative method for the fabrication of nano-scale silicon oxide.