Research on the tribological behavior of Ti3SiC2, a new type of machinable cermet material, in water-based lubrication systems (such as water hydraulic systems) and ethanol lubrication systems (eg, ethanol fuel systems). Ti3SiC2 sample was prepared by applying medium frequency hot-pressed sintering technology. Tribological behavior of Ti3SiC2/Si3N4 friction pair was explored with SRV-1 friction-abrasion testing machine in ball-on-disc mode. Surface morphology and composition phase were analyzed with scanning electron microscopy (SEM), X-ray photoelectron spectroscope (XPS) and X-ray diffraction spectrum. Ti3SiC2/Si3N4 had low coefficient of friction (0.14) and wear rate (10?7 mm3/(N?m)) in ethanol but high coefficient of friction (0.54) and wear rate (10?4 mm3/(N?m)) in pure water. The tribological properties of Ti3SiC2/Si3N4 could be degraded by a small amount of water (5 vol.%) in ethanol. Worn surface of Ti3SiC2 in ethanol was characterized by slight ploughing effect. As the water content in ethanol increased, pits caused by Ti3SiC2 grain pullout and spalling increased, and thereby wear rate increased rapidly. A large number of pits were present in pure water, and corresponding wear rate reached the maximum as well. Ethanol is a good low-viscosity fluid lubricant for Ti3SiC2/Si3N4 friction pair. Highly chemically active Si element on friction surface of ethanol has frictional chemical reaction with ethanol. The generated silanol polymer forms boundary lubrication on frictional contact interface. As a result, Ti3SiC2/Si3N4 friction pair has excellent lubrication and antifriction effect in the ethanol.