The adsorption-enhancing TiO₂-SBA-15 photocatalyst has been synthesized by an in situ etching displacement method, which possesses unique regular hexagonal pores and large specific surface area. The as-prepared TiO₂-SBA-15 can effectively adsorb and increase the concentration of pollutants in the photocatalyst and collision likelihood with the photogenerated radicals, thus improving the efficiency of photocatalytic organic degradation. The structure and morphology have been characterized by N₂ adsorption isotherms, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and scanning electron microscopy (SEM). These characterizations confirm that TiF₄ alcohol solution prefers to react with the internal surface of SBA-15 because of the Siphon effect. Fourier transform infrared (FTIR) spectra demonstrate that a Ti-O-Si bond formed after the reaction of TiF₄ with SBA-15, which reveals a wonderful combination of TiO₂ and SiO₂ even at low temperatures. Through this function, the nanocomposite TiO₂-SBA-15 could obviously improve the efficiency of photocatalytical removal of toluene in the gas phase.