Abstract: This paper systematically studied the composite lubrication effects between diamond-like carbon (DLC) film and fluid lubricants,and investigated the effects of viscosity,polarity and friction pairs on the friction behavior of lubricated DLC. It is found that the DLC exhibited good stability and affinity with the selected lubricants,while the friction behavior exhibited strong dependence on the lubricant polarity and friction pairs. In nonpolar alkenes,the contact pair exhibited strong influence on friction behavior. But in polar alcohols,both the viscosity and contacts pairs showed strong influence on tribological behavior. Thus,for the design of DLC based solid-liquid lubrication system,a comprehensive consideration about lubricant viscosity,polarity and friction pairs is needed.