Swollen and painful gums leading to swollen and painful lymph nodes may be caused by oral inflammation, oral cancer and other factors. 1. Oral inflammation: Inadequate oral cleaning, bacterial infection and other factors may lead to oral inflammation, such as gingivitis, pericoronitis, etc. The inflammation may invade the lymphatic tissues in the neck, leading to swollen and painful lymph nodes. 2. Oral cancer: the cause of this disease is still unclear, and it may be related to factors such as smoking and chewing betel nut, etc. After lymphatic metastasis of cancer cells, it may lead to enlarged lymph nodes and pain. There are many factors that lead to lymph node swelling and pain. It is suggested that patients should go to the hospital in time and take relevant treatments under the guidance of physicians to avoid delaying the condition.