Mesostructured ZrO2-TiO2 nanoparticles with different ZrO2 contents have been synthesized by an ionic liquid-assisted hydrothermal route. The prepared materials were characterized by means of X-ray diffraction (XRD), nitrogen adsorption-desorption, transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra analysis (DRS) and NH3-TPD technique. The obtained ZrO2-TiO2 materials exhibit large specific surface area and uniform pore sizes. Introduction of ZrO2 species can effectively suppress phase transformation from anatase to rutile and promote thermal stability of ZrO2-TiO2 materials. The photocatalytic activity of the ZrO2-TiO2 sample is higher than that of the TiO2 sample and commercially available Degussa P25. The high photocatalytic activity can be attributed to stronger adsorption in the ultraviolet region, higher specific area, smaller crystal size and increased surface OH groups. (C) 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.