Causes of enlarged submandibular lymph nodes include lymphadenitis, lymph node tuberculosis, malignant tumor metastasis, and lymphoma. Among them, malignant tumor metastasis or lymphoma may present with shoulder pain. Enlarged lymph nodes caused by lymphadenitis, lymph node tuberculosis are benign conditions and usually do not cause shoulder pain. Malignant tumors can develop lymph node metastasis and cause submandibular lymph node enlargement, such as thyroid cancer, nasopharyngeal carcinoma, parotid adenocarcinoma and so on. In addition to metastasis to lymph nodes, tumor may also have bone metastasis and cause local pain, which can be manifested as shoulder pain when metastasized to humerus or scapula. Enlarged submandibular lymph nodes are also common in hematologic malignancies, such as leukemia, lymphoma, multiple myeloma, etc., which can also occur bone metastasis or bone marrow infiltration and cause local pain. Patients with enlarged submandibular lymph nodes with shoulder pain are advised to go to the hospital as soon as possible to find out the cause and then give targeted treatment.