In aerospace and power generation, components will serve in high-temperature environments. In this work, the influence of temperature on the tribological performances of Cu/Ti3AlC2 composites was investigated from 25 °C to 700 °C. Cu/Ti3AlC2 composites were fabricated by hot-pressing at 800 °C. The friction coefficients of the composites were in the range of 0.19–0.28. From 25 °C to 300 °C, the wear-rates increased with temperature from 9.05 × 10−5 mm3/Nm to 110 × 10−5 mm3/Nm, and the wear-rate reached the highest value at 300 °C. Interestingly, the wear-rates plummeted to 30.8 × 10−5 mm3/Nm at 500 °C, and 31.2 × 10−5 mm3/Nm at 700 °C. It was found that tribofilms consisting of Ti3AlC2 and Cu2O covered on the wear surfaces at 25 °C and 100 °C. Plastic flow and material transfer occurred at 300 °C. From 500 °C to 700 °C, oxidation layers formed on the wear surfaces of the composites. For simplicity, a schematic of the tribological mechanisms is proposed.