Abstract：Objective：To study the administration rule of WU Yu in the treatment of liver cancer of spleen deficiency and phlegm coagulation type. Methods： Cases of liver cancer of spleen deficiency and phlegm coagulation type treated in the outpatient of WU Yu，a chief physician of Xiyuan Hospital of China Academy of Chinese Medical Sciences from September 1， 2017 to December 31，2018 were selected as study objects. Chinese Medicine Inheritance Auxiliary Platform(V2.5) was used to observe the high-frequency Chinese herbs and association rules，and cluster analysis of core herbs was conducted based on improved mutual information method and complex system entropy clustering，so as to explore core combinations and new prescriptions. Results： A total of 223 cases and 223 corresponding prescriptions were included， with 107 Chinese herbs applied. The most frequently used herbs were Poria(222)，Radix Pseudostellariae(221) and Bulbus Fritillariae Thunbergii(220). The property of those 107 Chinese herbs was mainly warm and neutral，and the flavor was mainly sweet，bitter and spicy， which mainly stayed in the spleen，lung，stomach，heart and liver collaterals. The top three herbal combinations with highest frequency were Radix Pseudostellariae- Poria(179)， Bulbus Fritillariae Thunbergii- Radix Pseudostellariae(178)， and Bulbus Fritillariae Thunbergii- Poria(178). There were 39 groups of related herbs with Confidence=1. The correlation degree was seven，and the penalty degree was four. Through hierarchical analysis by complex system entropy clustering，11 groups of core combinations including three to four kinds of herbs were obtained，with six new prescriptions. Conclusion：Prof. WU Yu’s treatment of liver cancer of spleen deficiency and phlegm coagulation type reflects the principle of fortifying the spleen with sweet- warm herbs and dissolving phlegm as well as dissipating masses，and Prof. WU modified the prescriptions to harmonize yin and yang as well as treat the root and branch simultaneously.