Abstract：Objectives：Traditional Chinese medicine inheritance support system V2.5 was used to analyze the medication rules of famous doctors in the treatment of lung cancer with dual deficiency of qi and yin and obstruction of phlegm- heat syndrome， so as to discover new prescriptions. Methods： The periodical literature of famous doctors at or above the provincial level about the treatment of lung cancer collected by CNKI from January 1996 to December 2019 was collected. The prescriptions that met the inclusion criteria were imported into the traditional Chinese medicine inheritance support system V2.5. The software was used for analyzing usage frequency of medicine，association rules and entropy clustering. Results：A total of 126 prescriptions meeting the inclusion criteria were selected， involving 272 kinds of Chinese medicines. Among them，Radix Astragali，Rhizoma Atractylodis Macrocephalae and Radix Ophiopogonis are commonly used for tonifying qi and yin； Herba Hedyotis Diffusae is commonly used for clearing heat and dissipating binds； Bulbus Fritillariae Thunbergii is commonly used for resolving phlegm，suppressing cough and calming panting；Poria is commonly used for inducing diuresis to drain dampness，and Pericarpium Citri Reticulatae is commonly used for regulating qi. Through association rule analysis，a total of 37 pairs of couplet medicines and 22 combinatorial rules were obtained，as well as the network diagram composed of Liujunzi tang and medicines such as Radix Astragali， Semen Coicis， Bulbus Fritillariae Thunbergii， Radix Ophiopogonis， Radix Glehniae，and Herba Hedyotis Diffusae. A total of 36 pairs of core combinations of medicines and 18 new prescriptions were obtained by entropy cluster analysis. Conclusion：The analysis results of administration rules of famous doctors in the treatment of lung cancer with dual deficiency of qi and yin and obstruction of phlegm- heat syndrome reflect the treatment idea of “treating both tip and root”. The tonification of deficiency is mainly to tonify the dual deficiency of qi and yin， followed by tonifying blood and yang；excess purgation is mainly to treat phlegm- dampness，blood stasis and heat toxin， followed by suppressing cough，calming panting，and regulating qi.