To further explore the changing temperature field and the failure mechanism of wet friction pairs, four evaluation indexes of mean temperature rise rate, maximum radial temperature difference, radial temperature non-uniformity coefficient and radial temperature deviation coefficient are introduced, and the evaluation system of sliding temperature rise characteristics is established. Then accelerated life tests are designed based on the actual working conditions. According to the variation role of friction coefficient and the maximum radial temperature difference, the different stages of sliding characteristics are divided. Based on the evaluation system, the role of sliding temperature rise characteristics are studied during running-in period, stable period and unstable period. The influence rules of speed, surface pressure and lubrication volume on temperature rise characteristics are analyzed in stable period. Moreover, the failure warning information of wet friction pairs is explored during unstable period. The study shows that, the evaluation system of sliding temperature rise characteristics can be used to evaluate the performance of sliding temperature, and the friction coefficient and the maximum radial temperature difference can be used as the indexes for judging running-in state of friction disc. The effect of surface pressure on temperature rise characteristic is the most significant compared with other factors. The temperature rise rate, the radial temperature difference and the radial heat dissipation difference increase significantly in unstable period.