Objective To compare the mean operative time and complications between the LigaSure device and Harmonic Scalpel during video-assisted endoscopic approaches thyroidectomy. Methods The clinical data of 684 cases performed Miccoli thyroidectomy by the same operation team from January 2007 to December 2011 in the department of general surgery，Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University were analyzed. Three hundred and forty-nine patients were used Harmonic Scalpel，335 patients were used LigaSure device. The mean operative time and complications （such as hematoma，transient hoarseness，permanent recurrent laryngeal nerve injury，and hypocalcemia） were compared between two groups. Results A total of 684 patients were included in the study，of whom 263 underwent total thyroidectomy and 421 underwent lobectomy. There were not significant differences of the operative time and the complications in both thyroidectomy and lobectomy between the LigaSure device and Harmonic Scalpel（P＞0.05）. Conclusions The uses of the LigaSure device and Harmonic Scalpel in thyroid surgery are safe and reliable，surgeons may choose surgical instruments by habits and medical equipments.