Natural orifice transluminal endoscopic surgery (NOTES), in which a flexible endoscope is used to perform operations that have traditionally required laparoscopic surgery, has garnered attention as a minimally invasive surgery that does not leave a surgical wound on the body. Among the various forms of NOTES, endoscopic full-thickness resection (EFTR) is an ultraminimally invasive endoscopic surgery that allows for radical resection, which is an extension of endoscopic submucosal dissection and involves full-thickness excision of a tumor of the gastrointestinal tract wall. With further development of the equipment, including full-thickness suture instruments, nonexposed EFTR could be a feasible surgical procedure.