Patients who were scheduled to undergo neck dissection due to head and neck cancer were eligible for this study. After receiving a detailed explanation, all patients signed an informed consent form before randomization. The study group were treated using the LigaSure vessel sealing system (Small Jaw®; Covidien, Colorado, USA) for dissection and hemostasis throughout the whole procedures during neck dissection. Relevant data included tumor-related variables, perioperative parameters, postoperative drainage status, postoperative subjective pain, and analgesic consumption amount were recorded and analyzed.