Abstract: Objective: To investigate medication rules of Coicis Semen-involved prescriptions in treating lung cancer through data mining. Methods: All of the clinical literature reports on treating lung cancer by Coicis Semen-involved prescriptions were retrieved, systematically collected and sorted out from China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database and Chinese Biomedical Literature Database. After the screening of compound data to establish database,the dosage of Coicis Semen and natures, flavors, channel entry and frequency of high-frequency Chinese herbs were counted,and the data were analyzed by association rule analysis and cluster analysis. Results:A total of 19 literatures and 22 Chinese herbal compounds were selected, involving 99 Chinese herbs. The main natures of the Chinese herbs were cold, warm and mild. The main flavors were sweet, bitter and acrid. The main channel entry were the lung, liver and spleen. The main categories of the Chinese herbs were heat-clearing herbs, deficiency-supplementing herbs, phlegm-dissolving and cough-relieving herbs, urination-promoting and dampness-percolating herbs, qi-regulating herbs, and blood-invigorating and stasis-dissolving herbs. High-frequency herbs included Astragali Radix, Glycyrrhizae Radix et Rhizoma, Atractylodis Macrocephalae Rhizoma, Pinelliae Rhizoma, Poria, etc. . The dosage of Coicis Semen was from 10 to 30 grams. A total of 14 core herbal combinations were obtained by association rule analysis. A new combination prescription was obtained by cluster analysis. Conclusion:The general principle of using Coicis Semen to treat lung cancer is to reinforce healthy qi and dispel pathogen and combine attack with supplementation. The mainly used Chinese herbs are sweet,bitter and acrid in nature. The main treatment methods are supplementing and boosting the spleen and lung, fortifying the spleen and dispelling dampness, invigorating blood and dissolving stasis, and drying dampness and dissolving phlegm. The dosage of Coicis Semen ranges from 10 to 30 grams,and the dosage can increase with the aggravation of lung cancer.