In this paper, Ti, Al and Ag films were deposited on SiO2 (100) using vacuum evaporation method and were modified by 100 keV C+ implantation using a dose of 1 X 10(17) ions/cm(2). The variations in structure, chemistry and tribological propel-ties were studied. It was found that C+ implantation had beneficial effect on both the tribological behavior and rupture load of the metal/SiO2 systems due to the enhancement in mechanical properties and interfacial adhesion between the films and substrates. Atomic force microscopy images showed the microstructure of nano-grains of the Ti film before and after C+ implantation. X-Ray diffraction and X-ray photoelectron spectrometer results revealed that TiC existed at the near-surface, and Ti-C solid solution existed in the film and the interfacial layer.