Abstract: Objective: To explore the causes of recurrent laryngeal nerve (RLN) trauma due to operations for thyroid lesion and the preventive measures.Methods: The surgical procedures for thyroid lesion,the correlation between whether the recurrent laryngeal nerve was isolated and protected in the operation and the recurrent laryngeal nerve trauma were analyzed retrospectively.Results: Three hundred and nineteen patients received complete resection.Three cases presented temporary trauma of recurrent laryngeal nerve,and no postoperative hemorrhoea or thyroid crisis occurred.Conclusions: The anatomy of the recurrent laryngeal nerve is complicated.The key to reducing RLN trauma is to know well the anatomy and the variation of recurrent laryngealn nerve,and to reveal the recurrent laryngeal nerve accordingly in the surgical operation for thyroid lesions.