Foreign bodies in the maxillary sinus are not uncommon. The traditional approach for removing such foreign bodies is Caldwell-Luc procedure. This report described that removal of tooth root from maxillary sinus with an aid of endoscopy. The patient was admitted. Under general anesthesia, the endoscopy was put into maxillary sinus via nasal inferior meatus and removal of tooth root through the previous extracted socket. The oroantral fistula was repaired with rotational palatal flap. Using the endoscopic approach, it will decrease the wound and complications of traditional open surgery. Submitting this case for further discussion of diagnosis and treatment.