Abstract： Objective： To discuss the inhibition effect of Clear Tianheshui method on fever due to endotoxin in young rabbits and its point specificity，and to study the relation between its related mechanism of fever subsidence and the changes in the contents of prostaglandin E2(PGE2) and cyclic adenosine monophosphate(cAMP) in hypothalamus. Methods：A total of 40 New Zealand young rabbits with the body mass of 1.2~1.8 kg were selected， half male and half female， and were randomly divided into the blank group， the model group， the Clear Tianheshui group， the non- point area group and the medicine group，eight rabbits in each group. The changes in the temperature of young rabbits and the contents of PGE2 and cAMP in hypothalamus were observed. Results： Except in the blank group and Clear Tianheshui group， there were two peaks of fever being found in all the other groups. Until the third hour， the temperature in the Clear Tianheshui group decreased to near normal. Compared with those in the blank group，the temperature and the contents of PGE2 and cAMP in hypothalamus in the model group were significantly increased(P＜0.01). When compared the temperature and the contents of PGE2 and cAMP in hypothalamus in the non-point area，there was no significant difference being found between the model group and the non-point area group. Compared with those in the model group，the temperature in the medicine group was significantly decreased(P＜0.05)， and the contents of PGE2 and cAMP in hypothalamus were both decreased(P＜0.05)； in the Clear Tianheshui group，the temperature was significantly decreased(P＜0.01)，and the contents of PGE2 and cAMP in hypothalamus were significantly decreased(P＜0.01). The temperature and the contents of PGE2 and cAMP in hypothalamus in the Clear Tianheshui group were all lower than those in the medicine group(P＜0.05). Conclusion：Clear Tianheshui method has significant effect of fever subsidence on fever due to endotoxin in young rabbits and point specificity. The medicine group also has effect of fever subsidence，which，however，is not as good as that in the Clear Tianheshui group and with slower curative effect. The mechanism may be the cooling effect caused by the inhibition of the contents of PGE2 and cAMP in hypothalamus.