In this paper, tribological tests for Ti3SiC2 sliding against low carbon steel were made on a block-on-disc type friction tester, with the normal pressures from 0.1 to 0.8 MPa and the sliding speed of 30 to 50 m/s. The surface state was observed and analyzed by SEM and XRD. A definite tribo-glazing layer was found over the worn surface of the Ti3SiC2 block, which seems to be primary reason for Ti3SiC2 to have comparatively lower friction coefficient and wear rate, because the tribo-glazing layer would be fusible under high frictional temperature. The tribo-glazing layer was the results of tribo-chemical oxidation reaction and the cause forming it could be the high frictional temperature and the mechanical catabolism in the surface of Ti3SiC2 during sliding friction. Due to the tribo-oxidation reaction is un-reversible and self-adaptive, the tribo-glazing layer in area and thickness are function of normal pressures and sliding speed.