Boys with persistent fever for 4 months, there may be tuberculosis, rheumatic fever, leukemia and other diseases, need to go to the hospital in a timely manner to check, clarify the cause, and standardized treatment, if necessary, bone marrow transplantation. 1. Tuberculosis: boys with persistent fever for 4 months, may be tuberculosis, that is, Mycobacterium tuberculosis infection of the lungs, in addition to fever can be accompanied by coughing sputum, hemoptysis, fatigue, etc., the treatment is mainly through the standardized use of anti-tuberculosis drugs to treat. 2. Rheumatic fever: rheumatic fever is mostly related to hemolytic streptococcal infection, which can be manifested as a persistent fever, accompanied by rash, joint pain and other symptoms, the treatment is mainly the use of antibiotics such as penicillin, as well as aspirin, glucocorticoids and other anti-rheumatic treatment. 3. leukemia: boy persistent fever for 4 months, may also be caused by leukemia, need to improve the examination, mainly through chemotherapy treatment, conditions allow for hematopoietic stem cell transplantation treatment. Boys with persistent fever for 4 months, may also be caused by other diseases, need to consult a doctor in time to clarify the cause of persistent fever, and then targeted treatment and treatment. The use of medication should follow the doctor’s instructions.