This is a case of anesthesia for a 49 year old woman with huge thyroid tumor who was admitted for total thyroidectomy. General anesthesia for thyroidectomy has traditionally involved tracheal intubation. But, we failed orotracheal intubation as in ability to insert a tracheal tube from the oropharynx into the trachea. After laryngoscopy was attempted three times, a laryngeal mask airway ProSealTM (PLMATM), size 3, was requested. The device was passed easily, and a patent airway was obtained. During general anesthesia, patient was mechanically ventilated through the PLMATM to airway pressures of approximately 20 cmH2O and positive pressure ventilation without air leaks was possible. Total thyroidectomy was performed without hypoxia and hypercarbia.