Abstract: Friction and wear tests for carbon/carbon composite were carried out on a high speed carrying current friction and wear tester, the friction coefficient, wear rate and worn surface morphology of the composite under the conditions of different currents, loads and sliding rates were studied, and the wear mechanism was analyzed, too. The results indicate that when the load was constant, the friction and wear properties of carbon/carbon composite first maintained good and then tended to deteriorate with the increase of current and sliding rate. When the current and sliding rate were constant, the friction and wear properties of carbon/carbon composite deteriorated under low or high load. With the temperature of friction surface increasing, the matrix of the composite was oxidized and the carbon fiber dropped and turned into wear debris and thus abrasive wear was induced. With the temperature raising further, the wear debris were softened and were grinded into carbon film at mechanical stress and thus adhesive wear was induced. The temperature increasing and high-velocity impacts destroyed the integrality of carbon film, thus, the friction and wear properties of carbon/carbon composite were worsened.