Fever in adults with pneumonia usually lasts anywhere from 3-5 days, and may last longer in some patients with lower immunity. The duration of fever in adults with pneumonia is related to the patient’s immunity, viral infectivity and promptness of treatment. In most adults, if the immune system is normal and the infection is mild, the fever usually lasts about 3-5 days. If the patient’s immunity is low, the infection is severe, the medication is inappropriate or the infection is not treated promptly and effectively, the fever and other symptoms may last longer. Therefore, patients with pneumonia fever are advised to choose targeted medications to control the infection as soon as possible after completing relevant tests. In addition, if the patient’s body temperature exceeds 38.5°C, physical cooling or symptomatic treatment with antipyretic drugs may be appropriate. In addition, patients with pneumonia need to take rest, drink more water, eat a light diet, and quit smoking and drinking during treatment. It is also recommended to seek medical attention for persistent high fever to avoid aggravation of the disease.