This paper presents a case of massive tongue swelling as a complication after an operation in the park bench position. A 43-year-old male who had undergone a resection of a mass in the petrous bone of the clivus showed massive tongue swelling after the surgery in the left park bench position. A direct compression of the bite block caused the swelling of tongue. Tongue swelling may become fatal if it progresses to an airway obstruction; therefore the intraoperative and postoperative management is important.