Abstract: The tribological properties of SiCH oil/TiN film composite system, which was prepared by multi-arc ion plating TiN film on substrate surface and SiCH lubrication oil combining technology, were studied by using a ball-ondisk tribometer. The wear mechanism was also discussed. The results show that SiCH oil maintained good frictionreducing and anti-wear properties for the friction pairs with both the disk and ball surfaces coated with TiN film. The good tribological properties were due to the good chemical stability and abrasive resistance. After 1.8×10⁶ cycles friction test, the partial decomposition of the SiCH oil and presence of trace amounts of Si-R-(CH₃)₃₃ in the process of vacuum sliding friction had no distinct effect on the lubricity of the SiCH oil. The wear lifetime the SiCH oil/TiN film composite system was longer than 1.8×10⁶ cycles.