The temperature characteristic and the effect of laser bleaching discolored teeth are reported in this paper. The temperature characteristics of the discolored teeth without bleaching agent and with bleaching agent are researched. The temperature of laser bleaching is controlled at 46 ℃. Laser power bleaching discolored teeth is applied in clinic and the results are successful with the special bleaching gel containing 35WHz02 and 6% magnesium carbonate.