Injury to the recurrent laryngeal nerve associated with thyroid surgery is mostly unilateral, but some patients may have bilateral injury to the recurrent laryngeal nerve as a result of simultaneous or sequential surgery on both lobes of the thyroid gland. Once bilateral laryngeal nerve injury occurs, it is often accompanied by significant respiratory distress and often requires emergency tracheotomy. Unilateral laryngeal nerve injury only shows hoarseness, choking cough and vocal fatigue, some patients about 3 months after surgery, because of the compensatory inversion of the contralateral vocal cords, their vocal quality significantly improved, vocal fatigue, hoarseness and choking cough significantly reduced, although can not reach the condition before the injury, but basically can meet the needs of daily communication, so most patients generally do not seek further treatment. However, there are still more patients in the injury 6 months later, the compensatory inward retraction of the contralateral vocal folds still can not effectively close the vocal folds, such as the injury side of the vocal folds external booth fixed, vocal folds tension decline appears vocal folds relaxation, and the healthy side of the vocal folds are not at the same level, etc., hoarseness, vocal fatigue and misaspiration, choking and coughing and other manifestations are still very obvious. The treatment of this type of patients is mainly aimed at promoting vocal fold closure, narrowing and eliminating the vocal fold gap. 1, treatment of unilateral laryngeal recurrent nerve injury 1.1 Type I thyroid chondroplasty Using local infiltration anesthesia, a small transverse incision is made at the level of the flat vocal cord in the affected neck, a small cartilage window is opened in the affected thyroid cartilage plate, the endochondral membrane is preserved, the endochondral membrane is peeled away from the cartilage plate, the affected vocal cord is pushed inward, and a sterile silicone block is filled between the endochondral membrane and the cartilage plate in the form of a thyroid cartilage piece or a wedge, so that the affected vocal cord is displaced toward the midline. The wedge-shaped implant promotes the narrowing of the posterior joint gap to maximize the elimination of the vocal fold gap. After filling the cartilage piece and silicone block, the patient is instructed to vocalize, and the surgeon and the patient evaluate the vocal satisfaction together. By adjusting the size and shape of the filling, when the vocal improvement is satisfactory, the filling can be fixed and the incision can be sutured to complete the surgery. The procedure is simple and easy to perform, with little pain for the patient, and the vocal improvement can be assessed intraoperatively, with positive and satisfactory results. However, the operation requires careful and gentle operation. If the endochondral membrane is damaged or the trauma is large, bleeding, unsatisfactory vocal correction and graft dislodgement may occur. 1.2 Vocal fold injection includes intra-vocal fold injection and paravocal fold injection, and paravocal fold injection is mainly used for unilateral recurrent laryngeal nerve injury. Autologous or allogeneic biomaterial is injected into the paravocalicular space to improve vocal fold closure, thereby improving vocalization and reducing false aspiration. The materials chosen for vocal fold injection are the key to this technique, from paraffin oil and Teflon in the early days to autologous fat, fascia, hyaluronic acid derivatives and hydroxyapatite nowadays. The materials chosen meet the requirements of no local allergy and rejection reactions, long-term stability of the injected material and no absorption. The procedure is mainly endoscopic injection under general anesthesia, which is less invasive and simple to operate. The injection volume and injection site are adjusted through endoscopic observation to achieve vocal fold closure. However, this method can only make the membrane part of the vocal cords threaded and fatigued. In patients with bilateral laryngeal nerve injury, the vocal folds are mostly fixed in the paramedian or midline position, and obvious inspiratory dyspnea is the most important manifestation. For these patients, the main goal of late treatment is not to improve vocal quality and misaspiration, but to enlarge the vocal cords, relieve dyspnea, remove the tracheal tube, and improve the quality of life. The following treatment modalities are mainly available. 2.1 Laser arytenoid chondroidectomy Currently, the CO2 laser is mainly used to excise the affected arytenoid cartilage intact under a supported laryngoscope from the anterior middle 2/3 of the affected vocal cord, outward to the arytenoid folds, backward over the arytenoid cartilage, and inward to the interarytenoid midline. A large slit is formed in the posterior part of the aryepiglottis to connect with the subaryepiglottic trachea for the purpose of relieving and improving dyspnea. The operation is performed under general anesthesia, which is simple and less painful for the patient, and is currently the most commonly used method. 2.2 Vocal fold resection The affected vocal fold can be resected by laser endoscopy or laryngeal laceration, and the vocal fold is often narrowed again in the long term. 2.3 Vocal fold adduction Through a cervical incision with an external laryngeal approach, the arytenoid cartilage is removed along the posterior edge of the thyroid cartilage, and the vocal fold protrusion suture is pulled out and fixed to the thyroid cartilage plate, allowing the vocal folds to be effectively enlarged. This is more difficult to perform than laser arytenoid cartilage excision. In conclusion, for those who have laryngeal nerve injury complicated by thyroid surgery and whose early nerve function cannot be recovered, further treatment should be actively sought through the above methods to maximize the improvement and quality of life of the patient.