Symptoms of radiation pneumonitis include coughing, coughing up sputum, dyspnea, and fever. Radiation pneumonitis is a sterile inflammation of the lungs caused by exposure to ionizing radiation and occurs mainly in patients with chest tumors who have been exposed to radiation therapy. Patients present with fever, cough, sputum, and atypical symptoms, usually occurring one to three months after radiation therapy. Symptoms start mildly with low-grade fever, cough and sputum, and gradually change to chest tightness, shortness of breath and then severe cough. For longer periods of time, pestle and mortar fingers may appear. If the symptoms worsen, dyspnea may appear. The X-ray shows ground glass changes and patchy hyperdensity. The prognosis of radiation pneumonitis is related to the dose and volume of radiation exposure, and most patients with radiation pneumonitis can recover in the later stages after active treatment. Therefore, once diagnosed with radiation pneumonitis, it is recommended to seek timely medical treatment and cooperate with doctors to take scientific treatment.