There is no clear clinical data indicating that the fever of acute respiratory tract infections usually goes down in a few days, and it needs to be judged according to the patient’s condition, and the fever can mostly go down in about 1~5 days. Usually patients with acute respiratory tract infections may have fever symptoms, but there is no clinical data indicating the specific time for the patient’s fever to subside. Generally for the condition is relatively mild, and take physical cooling measures in a timely manner, the fever can be reduced in about 1~2 days. However, for patients with fever over 38.5°C, the condition is relatively serious, and with timely treatment with antipyretic drugs, it may take 3~5 days for the fever to subside. However, for patients who do not take active treatment measures, it will lead to aggravation of the condition and prolongation of the fever. Patients with incomplete or inappropriate treatment may also suffer from prolonged illness, which may also lead to a relatively longer fever. Therefore, patients with fever symptoms need to take timely treatment measures according to the cause of the disease in order to avoid aggravation of the condition. It is recommended that patients with acute respiratory tract infections should follow the doctor’s instructions for the cause and symptomatic treatment in order to avoid delaying their condition.