Radiotherapy is one of the main treatments for tumors, and 70% of tumor patients in China will receive radiation therapy during the treatment process. For thoracic tumors such as lung cancer and esophageal cancer, normal lung tissues will inevitably be irradiated by radiation during radiotherapy, which will lead to the occurrence of radiation lung injury and may affect the efficacy of radiotherapy and the quality of life of patients. Currently, the highest incidence of radiation lung injury is 34% in foreign countries and 41.5% in China. Radiation lung injury mainly includes two conditions: early radiation pneumonia and late radiation pulmonary fibrosis. Western medicine treatment of radiation lung injury mainly uses the combination of hormones and antibiotics. Chinese medicine scholars generally agree that the etiology of radiation lung injury is due to internal invasion of heat and toxicity, burning the lung channels, injury to the fluid and depletion of qi, and interconnection of phlegm and stasis. According to the principle of “examine the evidence and seek the cause, examine the cause and treat”, clinical treatment mostly adopts the methods of clearing heat and detoxifying, nourishing Yin and moistening the lung, activating blood circulation and removing blood stasis. Traditional Chinese medicine has the advantages of positive efficacy and mild adverse effects in the treatment of radiation lung injury. When radiation lung injury occurs, the participation of Chinese medicine can not only improve the symptoms significantly, but also reduce or even avoid the use of hormones and antibiotics, thus reducing the adverse reactions caused by the application of hormones and antibiotics.