Enlarged lymph nodes in the neck of children may be caused by upper respiratory tract infection, lymphadenitis, malignant tumors and so on. 1. Local inflammatory stimulation caused by rhinitis, pharyngitis, tonsillitis and other upper respiratory tract infections can lead to hyperplasia and enlargement of cervical lymph nodes, at this time, the lymph nodes are mostly soft, without obvious pressure and pain, and good mobility, but after the primary disease is relieved, the symptom of enlarged lymph nodes will disappear as well. 2. If the lymph nodes in the neck are enlarged and painful, accompanied by high fever, or even limited neck movement, it may be caused by staphylococcus aureus or hemolytic streptococcus invading into the lymph nodes along the lymphatic vessels, causing acute bacterial lymph node or suppurative lymph node inflammation and so on. 3. Leukemia, lymphoma and other malignant tumors may also present with enlarged lymph nodes in the neck, which are tough and painless. It is recommended that children with enlarged lymph nodes in the neck should seek medical advice for a clear diagnosis and targeted treatment.