Hoarseness after thyroid surgery can be seen in the following cases: First, postoperative local bleeding and obvious hematoma formation, which compresses the recurrent laryngeal nerve, can lead to hoarseness, and if the hematoma is removed or absorbed in time, the patient’s symptoms can be improved. Secondly, for patients with malignant thyroid tumor, the lymph nodes in the neck need to be contoured during the operation, which will inevitably lead to damage to the laryngeal nerve. In addition, lymph node invasion to the recurrent laryngeal nerve may also manifest as hoarseness of speech, and this complication is irreversible. Thirdly, intraoperative adjacent side injuries, such as clamping or intraoperative ligature, will also lead to local injury and manifest as hoarseness of pronunciation, and some patients can gradually improve their symptoms after respiratory function exercise and pronunciation exercise, which should also be reviewed regularly.