Tumor is the category of “obstruction and accumulation” in Chinese medicine, and it is a modern multi-morbidity. According to Chinese medicine, the ideal health state of human body is “Yin and Yang secret”, and “if the righteousness exists inside, evil cannot dry up”. Zhang Jinyue of the Ming Dynasty pointed out that “people with deficient spleen and stomach and those with weakness and disorder have accumulated diseases”. The “Golden Guide to Medicine” also clearly states that “accumulation is caused by a deficiency of positive qi followed by the presence of evil qi”. If there is a deficiency of positive qi, together with the long-term disorders of diet, emotion, labor and rest, as well as the invasion of evil toxins and environmental pollution, the imbalance of yin and yang qi and blood in human body, and the abnormal function of internal organs and meridians, resulting in blood stasis, phlegm, heat toxins and gas knots, which may lead to the formation of L obstruction, i.e. tumor, and the composition and functional state of internal organs and meridians of yin and yang qi and blood in human body depends on the body constitution. Therefore, body constitution determines whether tumor will occur in an individual, and body constitution type affects tumor evidence and tumor treatment, and whether tumor recurrence and metastasis are related to body constitution type. Clinically, it is found that the occurrence, main evidence and treatment of tumor are all related to the type of constitution. For example, Zhou Xiaojun et al. investigated 400 cases of chronic nasopharyngitis, 80 cases of nasopharyngeal precancerous lesions and 150 patients with initial diagnosis of nasopharyngeal carcinoma with TCM physical evidence, and found that qi deficiency was significantly increased in nasopharyngeal carcinoma lesions, and disorders of cold and stasis were significantly increased in patients with initial diagnosis of nasopharyngeal carcinoma, and concluded that qi deficiency was an important factor in nasopharyngeal precancerous lesions, and cold and stasis were important in their pathogenesis. Zhang Xiangnong et al. conducted an epidemiological survey on 355 tumor patients with TCM constitution types and found that biased constitution occupied 82.54%, among which Yang deficiency and Qi deficiency constitution were more common in gastrointestinal tumors, and Qi deficiency constitution was more common in lung cancer, followed by Yang deficiency constitution. Different tumor patients have different physiological characteristics, which can provide better clinical ideas for treatment. It has been found that among lung cancer patients, those with qi deficiency constitution are more sensitive to chemotherapy, with the most obvious decrease in blood picture and the longest survival period, while those with phlegm-damp stagnation constitution are less sensitive to chemotherapy, with the highest percentage of deterioration and the shortest survival period. Moreover, studies have also found that those with deficient constitution, i.e. low immunity, are more prone to tumor metastasis. Therefore, it is important to actively regulate the body constitution and correct the bias in the prevention and treatment of tumor.