The thyroid gland is an important endocrine gland in the human body. The thyroid gland is located in the front of the neck and is butterfly-shaped in front of the tracheal 3 and 4 cricoid cartilage, moving up and down with swallowing, while there are more lymph node groups in the neck, and lymph node inflammation can also cause neck pain. So the pain on one side of the neck is not necessarily all about the thyroid gland. The pain on one side of the neck may have the following conditions: a. Subacute thyroiditis, a viral infection followed by subacute inflammation of the thyroid gland, can appear as pain in the front of the neck, which can radiate to the ipsilateral neck, ear, head, etc., and appear as pain on one side of the neck. Second, inflammation of the lymph nodes in the neck, when there is upper respiratory tract infection, inflammation of the oral and maxillofacial area and the pharynx, reactive enlargement of the lymph nodes in the neck with pain can occur, which can be manifested as pain on one side of the neck. Third, soft tissue pain in the neck, pain on one side of the neck may also be caused by soft tissue in the neck, cervical spondylosis, etc.