ObjectiveTo investigate the feasibility of dissecting the external branch of the superior laryngeal nerve using endoscopic thyroidectomy via gasless unilateral subclavian approach combined with intraoperative nerve monitoring. MethodsThe clinical data of 30 patients who underwent the gasless trans-subclavian approach endoscopic thyroidectomy in the Department of Head and Neck Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from October 2023 to February 2024 were retrospectively analyzed. ResultsAll operations were successfully completed under endoscopy approach without transfer to open surgery. A total of 29 cases of the external branch of superior laryngeal nerves were revealed in 30 cases, the rate of external branch of superior laryngeal nerve was 96.7%. The time for dissecting the external branch of the superior laryngeal nerve was 2－6 min (3.6±2.3) min. There was no obvious sound change related to the injury of the external branch of superior laryngeal nerve in postoperative patients. ConclusionFor the modified endoscopic thyroidectomy via gasless unilateral subclavian approach combined with intraoperative nerve monitoring, excellent anatomical protection of the superior laryngeal nerve branches can be obtained.