The TiO 2 supported tourmaline composites were prepared by a sol–gel method and used as a photocatalyst for the degradation of formaldehyde (HCHO). The composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), N 2 adsorption–desorption, Fourier transform infrared (FT-IR) spectroscopy and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The results indicate that the mixed-phase of anatase and rutile exists in the TiO 2 /tourmaline composites. The specific surface area of the TiO 2 /tourmaline composites is much higher than that of the pure TiO 2 . The TiO 2 /tourmaline composites exhibited excellent photocatalytic activity for the degradation of HCHO, which was 6 times higher than that of the pure TiO 2 . Moreover, the excellent photocatalytic activity of the composites was fully maintained after five photocatalytic cycles, which may be attributed to the physicochemical property of tourmaline and the mixed-phase of anatase and rutile in the TiO 2 /tourmaline composites.