Mechanical properties of carbon films deposited by plasma polymerization on different sub-strates were studied.Film hardness was measured to be approximately 20GPa.Adhesive scratch testsfound the critical load L,at which film failure occurred,of the films on silicon,glass,hard magneticrecording disc were 28,45 and 18N,respectively.No definite value was detected for the film on bear-ing steel substrate.Tribological study suggests that the friction coefficient of the films was in the rangeof 0.1—0.3.The wear rate of the carbon film was 1-2 orders of magnitude lower than that of thesubstrates.Micrographs of the wear tracks and the magnitude of the wear coefficients indicate that thelikely wear mechanism is the threebody abrasive wear.Films with stable low friction coefficient andsuperior wear resistance were obtained on silicon and steel substrates. Mechanical properties of carbon films deposited by plasma polymerization on different sub-strates were studied. Film hardness was measured to be approximately 20 GPa. Adhesive scratch tests found the critical load L, at which film failure occurred, of the films on silicon, glass, hard magnetic recording disc were 28, 45 and 18N, respectively. Non definite value was detected for the film on bear-ing steel substrate. Preliminary study suggests that the friction coefficient of the films was in the range of 0.1-0.3. The wear rate of the carbon film was 1-2 orders of magnitude lower than that of the substrates. Micrographs of the wear tracks and the magnitude of the wear coefficients indicate that the likely wear mechanism is the threebody abrasive wear. Films with stable low friction coefficient and superior wear resistance were obtained on silicon and steel substrates.