The friction and wear of self-mated Ti₃SiC₂ under unlubricated condition and lubrication of PbO powders from room temperature to 700 ℃ in a nitrogen flow are studied. The results show that compared to unlubricated condition, the friction coefficient of self-mated Ti₃SiC₂ under lubrication of PbO powders decreases from 0.9 to 0.3–0.5 and the wear rates for pin decreases from 10^_2–10^_3 to 10^_5–10^_7 mm³/ N m. The SEM and Raman results indicate the microstructure and chemical composition of tribofilm at high temperatures have a strong effect on the friction and wear of self-mated Ti₃SiC₂ under lubrication of PbO powders. The composition of tribofilm varies with tribochemical and thermal reactions happening between PbO and SiO₂/TiO₂ on the tribosurface. The composition of tribofilms are analyzed to be PbO at room temperature, PbO and Pb₃O₄ at 400 ℃, and PbTiO₃ and PbSiO₃ at 700 ℃. The PbSiO₃ is formed by tribochemical reaction while it cannot be formed under thermal condition.