A titania-silica nanocomposite system with six different compositions (1090, 2080, 4060,5050 , 6040, 8020 molar ratio of TiO 2 SiO 2 ) was prepared by a sol-gel method. Different experimental techniques such as XRD, TEM, EDAX, DTA and density measurements by Archimedes' method were used to characterize each composition. The synthesized specimens had two structural phases: (i) crystalline TiO 2 in anatase form; and (ii) a Si-O-Ti bonded glassy phase. TEM results showed that spherical shaped TiO 2 particles are dispersed in a disk-shaped Si-O-Ti bonded glassy matrix. This glassy matrix creates an anti-sintering effect, which controls the growth of the TiO 2 particles. The size of the TiO 2 crystallites vary with an increase of the sintering temperature and in the range 10-50 nm. At 1300°C, two types of structural modifications, (i) anatase to rutile and (ii) crystallization of SiO 2 , occur within the system. The calculated bulk density value increases with sintering temperature and also with an increase of TiO 2 concentration.