Abstract：Objective：To study the medication rules of Chinese medicine internal therapy to reduce the recurrence rate of plasma cell mastitis (PCM) through the Ancient and Modern Medical Records Cloud Platform. Methods：Based on the published literature on CNKI，Wanfang Database and VIP Database，the literature related to using Chinese medicine internal therapy to treat PCM published from 2012 to 2022 were collected and the literature database was then established. Data mining methods such as frequency statistics， cluster analysis and association rule analysis were used to analyze the medication rules of Chinese medicine in treating this disease. Results：A total of 64 literature were collected，and 56 literature were included after the same Chinese medicine prescriptions were excluded，in which there were totally 61 prescriptions. A total of 118 kinds of Chinese herbs were involved ， and the frequency of use was 722 times， among which seven kinds were used twenty or more than twenty times， namely， Bupleuri Radix， Glycyrrhizae Radix et Rhizoma， Taraxaci Herba， Angelicae Sinensis Radix， Paeoniae Radix Rubra，Salviae Miltiorrhizae Radix et Rhizoma，and Herba Hedyotis Diffusae. The four properties of the herbs were mainly cold； the five flavors were mainly bitter； the herbs mainly entered into the liver meridian； the herbal effect was mainly to clear heat and resolve toxins. Meanwhile， fourteen herbal combinations and three clustered prescriptions were obtained. Conclusion： In the medication of using Chinese medicine to reduce the recurrence rate of PCM，bitter-cold herbs are used to clear heat，which mainly enter into the liver meridian. The symptomatic treatment is mainly to clear heat，resolve toxins and disperse swelling， so as to relieve symptoms by dispersing swelling and relieving pain； the causal treatment is mainly to soothe the liver and move qi，invigorate blood and dissolve stasis，so as to adjust the pathological state of qi stagnation and blood stasis in the body to prevent or reduce disease recurrence. The three clustered prescriptions are aimed at the initial onset of acute mastitis caused by qi stagnation and blood stasis，the comedogenic mastitis caused by yang deficiency and cold coagulation，and the state of deficient healthy qi and lingering pathogens after the comedogenic mastitis ulcer. By data mining technology，the medication rule of Chinese medicine internal therapy to reduce the recurrence rate of PCM is summarized， providing reference for clinical optimization of prescriptions， improvement of curative effect and development of new prescriptions for treating PCM.