In a patient who underwent surgical excision of recurrent tumor of ovarian disgerminoma, small bowel injury following radiotherapy was treated by extensive excision of the small intestine followed by intravenous hyperalimentation (I.V.H.) and hyperbaric oxygen therapy. From its clinical course and treatment, we concluded that 1) In small bowel complication due to radiation injury, especially perforation of the small bowel, radical excision of the diseased segment is most promising, if the general and local conditions permit. 2) I.V.H. is effective for protecting and improving postoperative malnutrition after extensive excision of the small bowel. 3) Hyperbaric oxygen therapy is very effective for postoperative paralytic ileus in the case in which surgical operation cannot be performed. 4) Zinc deficiency as a complication of prolonged I.V.H. therapy must be protected. 5) It is necessary to study pathophysiology of short bowel syndrome following the extensive excision and to continue treatment and careful long-term follow-up.