In this study, Ta2O5-SiO2 Composite films with various proportions of Ta2O5 were prepared by radio frequency ion-beam sputtering deposition. The residual stress of each composite film was analyzed. The residual stresses of different graded-index-like layers made of composite films were studied. The results show that the residual stress of a single layered composite film was lower than that of pure SiO2 or a pure Ta2O5 film. Furthermore, when the composite film was made graded-index-like, the residual stress was reduced. (C) 2008 Elsevier B.V. All rights reserved.