A submucosal cyst in the pterygoid sinus is clinically known as a pterygoid sinus cyst and is usually not a major problem. The pterygoid sinus cyst is located deep in the sinus, and because the pterygoid sinus has more adjacent structures, such as the optic nerve, cavernous sinus, and pituitary gland, the cyst there may be asymptomatic when it is small. Mucinous cysts can compress the above structures and cause symptoms such as loss of vision, headache, and endocrine disorders. Therefore, cysts in the pterygoid sinus can be surgically removed if necessary. Currently, nasal endoscopic excision of pterygoid sinus cysts is mostly performed, and intraoperative attention still needs to be paid to the above-mentioned structures to avoid damage. It is also necessary to pay attention to severe bleeding because there is a pterygopalatine artery in the anterior wall of the pterygoid sinus, and once the bleeding is damaged, it is more difficult to stop the bleeding, and it needs to be operated carefully during the operation, and it can be healed one week after the operation.