Ulcerative colitis (UC) is one of the chronic inflammatory bowel diseases (IBD), characterized by a diffuse mucosal inflammation limited to the colon. Complications of UC include stricture, colorectal cancer, and toxic colitis. UC patients rarely present with a stenosis or fistula, and strictures develop in less than 5% of patients with UC. We present a patient with UC, accompanied by unusual complications that involved not only a stricture but also a fistula and abscess. A 49-year-old female was presented with a left flank pain and fever that had begun two weeks before admission. She had received a diagnosis of UC 20 years ago and had it treated for 2 years in a local hospital. However, she arbitrarily stopped visiting the hospital and relied on home remedies. An abdominopelvic CT scan revealed luminal narrowing and extra-peritoneal fistula formation in the descending colon. Fistula was connected with a subcutaneous abscess in the left flank. She had undergone total colectomy and ileo-anal anastomosis. On the pathologic exam, the long standing UC with severe stenosis was observed without malignant change. It cannot be emphasized enough that a correct therapeutic approach and an appropriate follow-up schedule are very important for patients with UC.