The tribological behavior of self-mated Ti3SiC2 is investigated from ambient temperature to 800 °C at a sliding speed of 0.01 m/s in air. The results show that at the temperatures lower than 300 °C, friction coefficient and wear rates are as high as 0.95 and 10−3 mm3/N m, respectively. With the temperature increasing to 600 °C, both the friction coefficient and wear rates show consecutive decrease. At 700 and 800 °C, friction coefficient and wear rates are 0.5 and 10−6 mm3/N m, respectively. According to the wear mechanism, the tribological behavior of Ti3SiC2 can be divided into three regimes: mechanical wear-dominated regime from ambient temperature to 300 °C characterized by pullout of grains; mixed wear regime (mechanical wear and oxidation wear) from 400 to 600 °C; and tribo-oxidation-dominated wear regime above 700 °C. The tribo-oxides on the worn surfaces involve oxides of Si and Ti. And, species transformation occurs to these two oxides with the increasing temperature. In the competition oxidation of elements Ti and Si, Si is preferably oxidized because of its high active position in the crystal structure. Additionally, plastic flow is another notable characteristic for the tribological behavior of self-mated Ti3SiC2.