To explore the characteristics and medication rules of the prescriptions for the treatment of abdominal masses in Chinese Medical Code.Methods:The prescriptions for the treatment of abdominal masses in the Chinese Medical Code were retrieved，and screened according to inclusion and exclusion criteria，and an Excel database was established to analyze frequency of medication，properties，taste and meridian tropism.The arules and arulesViz packages in R language were used for association rule analysis and visualization of screened prescriptions.IBM SPSS Modeler 18.0 software was used for complex network analysis，and SPSS Statistics 26.0 software was used for cluster analysis of the prescriptions.Results:A total of 426 prescriptions were selected，containing 303 types of herbs，with a total frequency of medication of 4075 times.There were four properties in 9 types of herbs with a total frequency of 3 214 times.There were five flavors in 8 types of herbs with a total frequency of 5 490 times.The total frequency of Twelve channels was 11 936.The top 3 drugs with high frequency of application in the treatment of abdominal masses were Muxiang，Rougui and Danggui.The drug pair with the highest correlation was Sanleng-Muxiang.According to the complex network analysis，the correlation between Muxiang-Rougui and Muxiang-Sanleng was strong.The cluster map showed that when Pearson's correlation was 20，drugs could be clustered into 5 categories.Conclusion:In the treatment of abdominal masses by doctors in the past dynasties，the drugs used were mainly warm in nature，and spicy and bitter in taste.The meridians focus on the spleen and stomach meridians，and their effects mainly include regulating qi，warming interior，and tonifying the body.Through the study of the medication rule in the treatment of abdominal masses in Chinese Medical Code，it provides a reference for the summary of clinical practice of traditional Chinese medicine in the treatment of abdominal mass-related diseases.