Da Chaihutang from the Treatise on Febrile Disease （Shanghanlun） has the function of harmonizing lesser Yang and discharging internal heat. It is formulated by ZHANG Zhongjing for the concurrent diseases of lesser Yang and Yang brightness and has been widely used in the treatment of digestive system diseases， especially malignant tumors. By review of the articles published in the last 20 years， this paper summarizes the application of Da Chaihutang in treating digestive system tumors from syndrome analysis， clinical research， and mechanism research. Da Chaihutang can treat the syndrome involving lesser Yang and Yang brightness in the digestive system， release interior and exterior to expel pathogen， and remove obstruction by conforming to the descending nature of the six fu-organs. In clinical practice， Da Chaihutang can directly treat digestive system malignant tumors such as liver cancer， pancreatic cancer， intestinal cancer， gastric cancer， and gallbladder cancer. In addition， it can relieve common complications of digestive system malignant tumors， such as cancerous fever， malignant obstructive jaundice， and constipation. Moreover， it can alleviate the adverse reactions caused by Western medical treatment， such as post-embolization syndrome， side effects of chemotherapy， and incomplete postoperative obstruction. Da Chaihutang is effective when used alone as it can relieve clinical symptoms， improve prognosis， and prolong survival of advanced patients and is safe and non-toxic， suitable for long-term use by tumor patients. Regarding the mechanism， Da Chaihutang can promote the apoptosis and inhibit the proliferation of tumor cells， reduce inflammation and inflammatory injury， and improve the liver function. The clear effect and mechanism confirms the anti-tumor effect of Da Chaihutang. This paper comprehensively describes the current research status of Da Chaihutang in the treatment of digestive system tumors and puts forward the deficiencies and improvement measures for the current research， aiming to provide reference for the application of this formula in treating digestive system tumors， the establishment of Chinese and Western medicine treatment schemes of tumors， and the research and development of anti-tumor drugs.