Currently, thyroidectomies are performed with very little morbidity. This study was undertaken to investigate whether the use of the harmonic scalpel during thyroid surgery has any advantage over the conventional technique. Eighty patients were randomly assigned to 2 groups. The patients in group 1 (n=40) underwent thyroidectomy performed with conventional knot tying and the electrocautery technique; in patients in group 2 (n=40), the harmonic scalpel was used for the procedure. Significant differences were observed between these 2 surgical techniques in terms of operative time, number of ligatures used, amount of bleeding, average length of incision, total amount of drainage fluid, and cosmetic satisfaction (P<.05). With the harmonic scalpel technique, there was a nearly 18% reduction in operative time. No significant differences were noted between mean hospital stay and postoperative pain (P>.05). No patient in either group had permanent recurrent laryngeal nerve palsy or hypoparathyroidism. The harmonic scalpel significantly shortens the duration of thyroidectomies; it can be used safely and effectively in thyroid surgery with no additional morbidity.