With the development of modern medicine and the progress of evidence-based medicine, there is now a basic consensus on whether tumor patients need adjuvant radiotherapy after surgery. However, whether Chinese medicine treatment is needed or not still bothers many patients. They think that surgery has removed the tumor, and postoperative adjuvant chemotherapy or radiotherapy for high-risk patients will kill the residual and escaped tumor cells, so is it redundant to carry out Chinese medicine treatment again? Is it optimal for postoperative patients to only undergo regular review and then treat the tumor when it is found to have recurred? In this paper, the significance and application of Chinese medicine in post-operative tumor treatment are explained from the following aspects. I. Importance of Chinese medicine treatment after tumor surgery How does tumor arise? Modern medicine believes that tumor and human organism are “seed-soil” relationship, i.e. tumor cells (seeds) grow and develop in the suitable internal environment (soil) of the organism. The formation of the internal environment of the body which is conducive to the generation and development of tumor is a long process. A few hours of surgery only removes the result of the growth and development of tumor cells, but does not change the internal environment of the body, so it is necessary to further improve the “soil” to prevent the recurrence of tumor. According to Chinese medicine, tumor is caused by the deficiency of positive qi in the body, as well as the feeling of evil and poison, depression, diet damage and old diseases, which leads to the dysfunction of internal organs, abnormal operation of qi, blood and fluid, resulting in pathological changes such as qi stagnation, blood stasis, phlegm coagulation, dampness and heat poison, which are accumulated in the internal organs and tissues, fighting with each other, accumulating over time and gradually becoming tumor. The deficiency of positive qi is the root cause of tumor, such as the cloud of “External Medical Cases”: “If positive qi is deficient, it becomes rock”. Therefore, the causes of tumor (deficiency of positive qi and long detention of evil toxins) cannot be removed by surgery, but the causes can be eliminated by adjusting the imbalance of yin and yang, Qi and blood, and imbalance of internal organs function through Chinese medicine, so as to prevent the recurrence of tumor. A large number of studies have confirmed that Chinese medicine can improve the postoperative survival quality of tumor patients and enhance their postoperative recovery ability; Chinese medicine can influence the level of cellular immune expression and speed up the recovery of immune function of tumor patients after surgery, so as to achieve the purpose of cancer prevention and tumor suppression. (1) Early postoperative tumor: when the gastrointestinal function recovers after surgery, the patient can be treated with Chinese medicine for 2-3 months to promote recovery as soon as possible. Then, if the patient’s indicators are normal and there are no uncomfortable symptoms, consider that the patient’s disease is early and the positive energy can still fight against the evil, so the adjuvant treatment with Chinese medicine can be suspended. (2) Mid-term post-operative tumor: adjuvant therapy is needed, especially for patients with high-risk recurrence. In addition to 4-6 cycles (about 3-6 months) of chemotherapy or radiotherapy after surgery to “get rid of the evil”, it is well known that radiotherapy can kill tumor cells and also damage normal cells of the body. For example, after radiotherapy, there are symptoms of functional damage, such as fatigue, weakness, loss of hair and immunity, as well as gastrointestinal reactions and hematotoxicity, such as nausea, vomiting, poor appetite, diarrhea, decrease of white blood cells, etc.; different signs of gastric disharmony, deficiency of qi and blood, and deficiency of qi and yin, such as radiation dermatitis and radiation esophagitis. At this stage, Chinese medicine should be given to support and regulate the main treatment, improve the patient’s quality of life, reduce the adverse reactions of blood and digestive system, improve the body’s immune function, and achieve the purpose of supporting and increasing the effectiveness and reducing toxicity. After the completion of postoperative adjuvant radiotherapy, for patients who are asymptomatic and have no obvious abnormalities in various examinations, consider giving 2-3 years of anti-tumor treatment with traditional Chinese medicine to prevent recurrence and prolong survival. If the disease is stable and there is no recurrence or metastasis, the dose of Chinese medicine can be reduced or consolidated in intervals after 2-3 years of treatment. For patients with uncomfortable symptoms or abnormal indexes, those with higher possibility of tumor recurrence should be given 5 years of adjuvant treatment with traditional Chinese medicine to improve patients’ survival quality, reduce fear and prevent recurrence. As for whether to stop the medicine at 5 years after the onset of the disease, it needs to be analyzed specifically with the statistical data of the disease and cannot be generalized. Some people propose that in order to change the soil of tumor growth, lifelong medication is needed, which lacks sufficient scientific basis. Usually, 2-3 years after surgery is the peak period of recurrence for tumor patients. If adjuvant therapy with traditional Chinese medicine is adhered to for 2-3 years, the tumor recurrence rate of patients will be significantly reduced and the survival rate and quality of survival will be significantly improved. During the 5-year follow-up period after tumor surgery, TCM treatment is also involved throughout. Individual tumors (breast cancer) need 10 years of follow-up. (3) Post-palliative surgery: The so-called palliative surgery refers to the incomplete removal of primary lesions and regional lymph nodes for patients with advanced tumors, with the aim of improving the quality of survival, alleviating the pain caused by tumors, reducing or preventing complications (pain, bleeding, infection, dysphagia, vomiting, intestinal obstruction, dyspnea, urinary closure, etc.) and temporarily controlling tumor growth, such patients’ lesions have not completely disappeared after surgery. Those who are physically fit should continue chemotherapy and radiotherapy; if they are physically weak, they should be given bioimmunotherapy, Chinese medicine maintenance and conditioning, and comprehensive treatment such as helping to dispel evil. 2.According to the underlying disease: According to Chinese medicine, “if the righteousness exists inside, the evil cannot dry up”, which means that if a person’s righteousness is strong, it is not easy for the evil to attack the body and cause disease. On the contrary, if the body is deficient and the righteousness is not enough, the evil and poison will easily stay in the body and will not be dispelled for a long time, then the disease will develop. Whether a person will suffer from tumor or not depends largely on whether the internal environment of the body is conducive to the growth and development of tumor. Therefore, patients who also suffer from basic diseases such as hypertension, heart disease, diabetes, etc. and have poor immunity, i.e. imbalance of yin and yang, imbalance of qi and blood, should insist on taking traditional Chinese medicine after tumor surgery, which can control and treat these basic diseases and adjust the balance of the body on the one hand, and help to support the righteousness and anti-tumor and prevent recurrence on the other hand.