Objective: To analyze the composing principles of the prescriptions for lung abscess collected in the book of 'The Prescription of Traditional Chinese Medicine Dictionary’ using TCM inheritance system. Method: The prescriptions used for lung abscess in the 'book of The Prescription of Traditional Chinese Medicine Dictionary’ were collected

the composing principles were analyzed using revised mutual information

complex system entropy cluster and unsupervised hierarchical clustering in the TCM inheritance system after data entry. Result: Based on the analysis on 132 cases of prescriptions

the frequency of each herb included in the database was computed

46 core combinations and 8 new prescriptions weree mined from the database. Conclusion: TCM inheritance system can be used for entry

administration

search and analysis of the prescriptions and is a helpful tool for the research of traditional Chinese medicine.