Whether lymph node 29mm*5mm is serious is related to the primary disease. Lymph node 29mm*5mm is serious in terms of enlargement. Infection is a common cause of enlarged lymph nodes, the symptoms are generally more obvious, patients with a more acute onset of symptoms such as redness, swelling, heat and pain in the lymph nodes, such as patients with a slow onset of the disease and a long course of the disease should be wary of tumors. If the symptoms are caused by peripheral inflammation and infection, it is usually necessary to actively treat the primary disease. Generally, after treatment, most patients’ lymph node enlargement can subside slowly. In some patients, enlarged lymph nodes may be caused by metastasis of malignant tumors such as lymphoma, lung cancer, nasopharyngeal cancer, intestinal cancer, stomach cancer, etc. These cases are often more serious and patients need to take active treatment. These cases are often more serious, and patients need to identify the primary cancer and carry out active anti-tumor treatment. If you find enlarged lymph nodes, you should go to the hospital in time, complete the examination, make a clear diagnosis and then give active treatment, so as to avoid delaying the condition.