Abstract: The high temperature friction and wear behaviors and failure mechanism of wet multi-disc clutch were studied by high temperature pin-on-disc tests.The results show that with the temperature rising from 120 ℃to 420 ℃, the friction coefficient shows a trend of rapid increase first and then gradually decrease.When the temperature is lower than 345 ℃, it is mainly abrasive wear and ploughing wear, with less wear and less fluctuation of friction coefficient.When the temperature is higher than 345 ℃, the adhesive wear begins to appear on the surface of the friction pair, the wear amount increases sharply, and the friction coefficient fluctuates violently.Therefore, the reasonable working temperature of wet multi-disc clutch should be controlled within 345 ℃.