Lymph nodes are important organs of the body to fight against diseases, and they will increase in size when invaded by germs. Therefore, some parents always feel very nervous when they unintentionally touch their children’s enlarged lymph nodes, thinking that their children have a disease or even a tumor, and seek medical help everywhere and do many complicated tests. Sometimes the enlarged lymph nodes are the signs of some diseases, such as tuberculosis and malignant tumor, but sometimes they are not diseases, especially the enlarged lymph nodes that occur in pediatric period are usually normal. Most lymph nodes will naturally shrink and become less noticeable when the child passes puberty. Why do children have normal lymph node enlargement? This is because when children are born, the lymphatic system is not yet well developed, and the lymphatic tissues of the whole body develop fastest during early childhood and stop growing after puberty. Many children have normal lymph nodes that can be palpated in the neck, armpits, and groin. In general, a slight enlargement of the lymph nodes is sufficient to resist the invasion of germs, and the lymph nodes at this time are not diseased and do not need treatment, but the ability of the lymph nodes to resist infection is limited, and if too many germs enter the body, the lymph nodes will become pathologically enlarged. The enlargement of local lymph nodes reflects the lesion of the corresponding part of the tissue. The channels for bacterial viruses to invade children are mainly the mouth and nose, so the lymph nodes in the neck are often enlarged; for example, if the hands and feet are infected, there will be enlarged lymph nodes in the armpits or groin. Generally speaking, the diameter of normal lymph nodes is mostly within 0.5cm, with soft texture, smooth surface and no adhesion with surrounding tissues. If the lymph nodes are mildly enlarged, soft in texture, active and not accompanied by other symptoms, no treatment is needed for the time being, and their changes should be closely observed, and if they do not increase in size or gradually become smaller, they can continue to be observed; if the enlarged lymph nodes are larger, more, in bunches, hard in texture, growing rapidly, adhering to the surrounding tissues, accompanied by fever, wasting and other symptoms, they should be promptly visited to the hospital and alerted to the possibility of serious diseases such as malignant tumors.