Objective: To study the prescription and medication rule of Professor Hua Baojin in the treatment of colorectal cancer through data mining, so as to provide reference for clinical treatment of colorectal cancer. Methods: The outpatient medical records of Professor Hua Baojin from June 2015 to October 2020 in Guang\'anmen Hospital, China Academy of Chinese Medical Sciences were collected. TCM Inheritance Support Platform (V2.5) was used to analyze high-frequency drugs, drug properties, flavors, belonging meridians, common drug combinations, core combinations and new prescriptions. Results: A total of 500 prescriptions were included, involving 222 traditional Chinese medicines and 38 high-frequency (≥ 100) medicines, including Atractylodes, Poria cocos, Ginger, etc. The most common medicinal properties of drugs were warm, cold and mild, flavors were sweet, bitter and pungent, belonging meridians were spleen, stomach, liver and lung meridians. 36 groups of common drug combinations and 20 association rules were obtained by data mining, and 18 core combinations and 9 new prescriptions were evolved. Conclusion: Professor Hua Baojin takes recuperating spleen and stomach as the core in the treatment of colorectal cancer, attaching importance to regulating the rise and fall of qi, adding and subtracting on the basis of Xiangsha Liujunzi Decoction, flexibly selecting the drugs of dispelling blood stasis, resolving phlegm, detoxification and loose knots, and using both cold and warm in the prescription, tonifying and reducing at the same time.