Objective: To study the nature and flavour of LIU Wan-su’ drug application and the tendency of cold or warm in his prescription; analyze LIU Wan-su’s medical sect by the index of prescription metrology. Methods: Combining the traditional documents with prescription metrology, selecting three doctors before or after LIU Wan-su in Jin and Yuan Dynasty as comparison to expose the characteristic of prescription metrology in his prescription. Results: Wen tonic frequency of each prescription on average, LI Dong-yuan(1.10),ZHU Dan-xi(0.97), LIU Wan-su (0.77), ZHANG Zi-he(0.65); Han tonic frequency of each prescription, LI Dong-yuan (1.34),ZHANG Zi-he (1.00), LIU Wan-su (0.94), ZHU Dan-xi(0.80);Cool and warm drug ratio of four sects in Jin and Yuan Dyanstay, ZHU Dan-xi (0.97),LI Dong-yuan(0.83), LIU Wan-su (0.82), ZHNAG Zi-he (0.58).Cool and warm prescription ratio, ZHANG Zi-he(1.50), LIU Wan-su (0.87), LI Dong-yuan(0.76), ZHU Dan-xi (0.50).Conclusion: As the exponent of "theory of fi re and hot", it will be better to classify LIU Wan-su as " Hejian sect" since his drug application was not limited within cold and cool. To some extent, it is more important to judge a Chinese traditional doctor by syndrome identifi cation rather than only by his drug frequency.