Daily afternoon fever is usually considered for the following four etiologies: First, infectious diseases, such as persistent respiratory tract infections or gastrointestinal tract infections and urinary tract infections, can present intermittent fever, especially in the late afternoon, when fever is evident from 13:00-16:00 pm. Second, tuberculosis causes such as common pulmonary tuberculosis, intestinal tuberculosis and tuberculin infection of other organs will also commonly be followed by daily afternoon fever, usually particularly significant in the afternoon, from 14:00 to 19:00. Third, some connective tissue diseases and immune system diseases, hematologic diseases, and tumors can also lead to significant daily afternoon fever, but predominantly sustained moderate to high fever. Fourth, having rheumatic fever can also trigger daily afternoon fever.