Mesoporous titanium dioxide (TiO2) materials have been synthesized by a novel simple, template-free synthetic approach, which was carried out via nitric acid-catalyzed hydrolysis and polycondensation reactions of titanium(IV) n-butoxide. The as-prepared and calcinated mesoporous TiO2 materials are characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), and N2 adsorption/desorption measurements. The as-prepared amorphous TiO2 possesses a high BET surface area of 470 m2 g−1 and a pore volume of 0.28 cm3 g−1. After calcinations at 450 °C, anatase mesoporous TiO2 is formed with a BET surface area of 106 m2 g−1 and an average pore size of 4.8 nm. Avoidance of the structure-directing template during the synthesis of mesoporous TiO2 is of significant importance for application from both environmental and industrial points of view.