Normal body lymph nodes are accessible, rarely more than 1 cm, and rarely multiple fused. No matter what kind of lymph nodes are large, it is recommended to go to a specialized hospital with pediatric qualifications. If the lymph nodes are septic, surgical incision and drainage is needed, or if tumor lymph node enlargement is suspected, surgical excision and biopsy is needed, and tuberculosis requires anti-TB treatment from the infectious disease department. Ultrasound can help to diagnose whether the lymph nodes are necrotic or septic. Lymphadenopathy is mostly caused by pharyngitis, rhinitis or surrounding potential inflammation, with pain is mostly inflammation, without pain, other lesions should be suspected. If tumor cannot be ruled out, biopsy can be performed to clarify. Chronic lymphadenopathy is painless and does not subside for a long time without significant enlargement, often due to lymph nodes? If chronic inflammation exists in the drainage area, such as chronic pharyngitis and rhinitis, the efficacy of antimicrobial therapy is not significant, so it is crucial to enhance physical fitness and treat the original disease such as chronic pharyngitis and rhinitis. There is no need to pay excessive attention to the lymph nodes. Long-term painless enlargement of lymph nodes beyond normal size needs to be differentiated from tumors, and if progressive painless enlargement beyond normal volume in a short period of time should be alerted, the only way to determine the diagnosis is biopsy. Hyperplastic enlargement of lymph nodes is most often seen in young children/children as a normal physiological change or occurs after recovery from an inflammatory lesion, and in some cases can persist for several years. Especially in infants and children, the postauricular and retrooccipital lymph nodes are mostly palpable, but mobile, painless, mostly non-fused or more than 1 cm in diameter. Mesenteric lymphadenitis should theoretically be diagnosed by pathology as the gold standard. Ultrasound can describe the size of mesenteric lymph nodes, and large mesenteric lymph nodes can be seen in normal children with hyperplastic lymph nodes, those with systemic viral bacterial infections, local inflammation in the abdominal cavity, tumors, etc., the latter two in most cases In most cases the latter two require a surgical consultation.