Colorectal cancer is a common malignant tumor in the digestive system， ranking third in incidence and second in the cause of death worldwide. In recent years， the incidence of colorectal cancer is on the rise， and the age of patients with colorectal cancer tends to be younger， with a heavy cancer burden. It is of great significance to prevent the occurrence， development， recurrence， and metastasis of colorectal cancer to reduce the incidence and mortality of colorectal cancer. Patriniae Herba has the effects of clearing heat， removing toxins， eliminating carbuncle， and discharging pus and shows good therapeutic efficacy on inflammatory bowel disease， digestive tract tumors， pelvic inflammation， gynecological tumor， and so on. Patriniae Herba is often used in the clinical treatment of colorectal cancer， but its mechanism of action is not clear. Modern studies have found that Patriniae Herba contains triterpenoids， saponins， iridoids， flavonoids， and other chemical components， with antioxidant， anti-tumor， anti-bacterial， and other pharmacological effects. The main anti-tumor components of Patriniae Herba are flavonoids. The analysis of network pharmacology and the spectrum-effect relationship has suggested that quercetin， luteolin， apigenin， isoorientin， and isovitexin play a major role in inhibiting the occurrence and development of colorectal cancer. In vivo and in vitro studies have shown that flavonoids in Patriniae Herba can play an anti-tumor role in various ways， such as preventing precancerous lesions of colorectal cancer， inhibiting the growth and proliferation of cancer cells， blocking cancer cell cycle， promoting cancer cell apoptosis， and reversing drug resistance of colorectal cancer. The oral availability of flavonoids is low. The gut is the main metabolic site of flavonoids in the body， its metabolic pathway is closely related to gut microbiota. This paper reviewed the anti-tumor mechanism of flavonoids and their influence on gut microbiota to provide a reference for further research on the mechanism of Patriniae Herba against colorectal cancer and its clinical application.