Titania (TiO2) films were synthesized on MgAl6O10 (100) substrates by high vacuum metalorganic chemical vapor deposition (MOCVD). The crystal structures, surface and interface morphologies as well as the optical properties of the obtained TiO2 films depending on substrate temperature were studied in detail. A single-crystal anatase TiO2 (a-TiO2) film was obtained at the substrate temperature of 550°C. The epitaxial relationship between the a-TiO2 film and MgAl6O10 (100) substrate was a-TiO2 (001) || MgAl6O10 (100) with a-TiO2 [100] || MgAl6O10 [001]. The a-TiO2 film showed an average transmittance of 95.1% in the visible range, and an optical band gap of 3.46eV. The refractive indexes and extinction coefficients of the obtained TiO2 films as a function of wavelength were analyzed. A broad photoluminescence peak centered at 535nm was observed at room temperature and the corresponding luminescence mechanisms were discussed.