A 75-year-old man presented with bleeding ileostomy stoma 20 years after total colectomy and end ileostomy for chronic ulcerative colitis. On physical examination, the stoma was mass-like and firm with friable mucosa. Wedge biopsy of the ileostomy stoma revealed well-differentiated neuroendocrine tumor (intermediate grade). Ga-DOTATATE PET/CT showed mass-like focal radiotracer uptake at the ileostomy site without radiotracer-avid lymphadenopathy or distant metastatic disease. No additional sites of neoplasm in the gastrointestinal tract were further identified by endoscopy. The diagnosis of isolated primary neuroendocrine tumor of the ileostomy stoma was confirmed, an extremely rare entity.