The appearance of afternoon persistent fever, need to consider the possible existence of infectious diseases, if the persistence of afternoon fever, other time fever is not very obvious, first of all, need to carry out the relevant laboratory tests to rule out the possible existence of infectious lesions, such as mycobacterium tuberculosis infection. Secondly, non-infectious fever, such as leukemia, lymphoma, malignant tumors, as well as systemic lupus erythematosus, rheumatic fever, hyperthyroidism and other causes of thermoregulatory disorders. Finally, it is important to consider whether menopausal women with menopausal syndrome, caused by vegetative nerve dysfunction, can also appear afternoon fever, but clinically it is often manifested as a low fever. When the afternoon fever always occurs, we should actively seek medical attention to clarify the cause and timely treatment.