X-ray photoelectron spectrosoopy has been used to analyse the composition and valence of TiO2 films. The TiO2 films are deposited on the Si substrate to avoid spectrum-peak shift induced by electricity. It is shown that main composition in both absorptive TiO2 film and transparent TiO2 film are TiO2. In the absorptive TiO2 film partial TiO2 is changes into titanium oxide with low valence. The large amount of C on the surface of TiO2 film is responsible for the surface absorption.