Amorphous TiO2 thin films and TiO2/ZnFe2O4 composite films were deposited by r.f. magnetron sputtering. The influence of postdeposition annealing on the structural and optical properties was studied. It was established that the anatase single phase exists between 250 and 800 degrees C for the TiO2 thin films, and between 450 and 650 degrees C for the composite films. The absorption edge of TiO2 thin films and composite films exhibits a blue shift with decreasing annealing temperature. The absorption edge of composite films has moved to visible spectrum range, and a very large red shift occurs in comparison with TiO2 thin films.