Four-year-old children with recurrent fever can be seen in physiological factors, at this time without special treatment; can also be seen in tuberculosis and other infectious diseases, systemic lupus erythematosus and other autoimmune diseases or leukemia and other malignant tumors, more drug therapy. 1. Physiological factors: in breastfeeding, after meals, exercise, crying, too thick clothing, high room temperature and emotional fluctuations, etc., can make the body temperature slightly as high as 37.5 ℃, at this time, we need to pay attention to the increase or decrease of clothing, reduce indoor temperature, etc., and dynamic monitoring of body temperature changes. 2. Tuberculosis: can also make the child repeatedly fever, mainly manifested as afternoon low fever, night sweats and other discomforts, at this time need to follow the medical advice to use isoniazid, rifampicin, ethambutol, streptomycin and other drugs treatment. 3. Systemic lupus erythematosus (SLE): it can also cause recurrent fever in children, accompanied by facial erythema, arthralgia and other manifestations. In the acute stage, bed rest should be provided, nutrition should be strengthened, and sun exposure should be avoided. It can be treated with ibuprofen, hydroxychloroquine, methylprednisolone, cyclophosphamide and other drugs as prescribed by the doctor. 4. Leukemia: it can also make babies have recurrent fever, and this disease is mainly treated with chemotherapy, and commonly used drugs include vincristine, erythromycin, mentholase, prednisone, cyclophosphamide and so on. Hematopoietic stem cell transplantation is also available. For fever but temperature <38.5℃, physical cooling can be chosen; for temperature ≥38.5℃, antipyretic drugs such as ibuprofen can be used as prescribed by the doctor. The above drugs should be used under the guidance of physicians, avoid self-medication. There are many other causes of recurrent fever in children, and it is recommended to actively seek medical attention to avoid delaying the condition.