Objective To analyze the dosage form, functional indications, prescriptions and core combinations of the prescriptions for the treatment of aphthous ulcers, and to provide reference for the clinical research and treatment of the syndrome differentiation of mouth sores and the development of new drugs for prescription preparations. Methods To collect the treatment of aphthous ulcers in the“Pharmaceutical Standards of the Ministry of Health of the People’s Republic of China, Chinese Medicine Formulations”(hereinafter referred to as “Chinese Medicine Formulations”) and “Pharmacopoeia of the People’s Republic of China: 2015 Edition”(hereinafter referred to as the“Chinese Pharmacopoeia” in 2015) The name, prescription, dosage form, function and indication of the prescription preparation were entered into Microsoft Excel and Chinese Medicine Heritage Supporting Platform (V2.5), and the frequency of drug use was statistically analyzed. The Apriori algorithm and association rules were used to analyze the core composition of the prescription (support degree is 10%, confidence 100%); The Apriori algorithm and association rules were used to analyze the core composition of the prescription (support degree is 10%, confidence is 100%); the entropy clustering algorithm is used to calculate the correlation coefficient between 2-3 different components(support degree is 8, penalty degree is 2)； The intrinsic core combination and the new party combination are extracted according to the unsupervised entropy hierarchical clustering method. Results Excavated 86 kinds of prescription preparations and their prescriptions, including pills, powders, tablets, etc., including 148 flavors of drugs, the frequency of use is higher for borneol, licorice, rhubarb, jaundice, etc. Mainly due to the heart, stomach and spleen, the treatment syndromes are more hot toxic stagnation syndrome, heat poisoning throat syndrome, etc. Common core compatibility includes “Huangqi-Dahuang” and “Huanglian-licorice”, etc. “Pearl-Chuan Fritillaria-rush-Tianhua powder-myrrh” and so on. Conclusion Using data mining to analyze the prescriptions of prescriptions for the treatment of aphthous ulcers, the core drugs are combined into a new prescription, which can provide basis and reference for clinical syndrome differentiation and research and development of treatment of aphthous prescriptions and new drugs.