A 56 year old male patient with diarrhea, vomiting, and severe abdominal pain was hospitalized to our institution. Plain x-ray films showed obstruction of the small bowel; ultrasonography, peritoneal fluids and a dilated intestine with thicken walls; and contrast-enhanced ultrasonography, a clear whirlpool sign. These findings led to a diagnosis of intestinal volvulus with ischemic change, and emergency surgery was carried out. Intestinal ischemia of the loop was found at laparotomy. Because of the viability of the intestine after the volvulus was untwisted, however, intestinal resection was not necessary. Contrastenhanced ultrasonography may prove valuable in diagnosing intestinal volvulus and small-bowel obstruction with or without vascular flow in the intestinal walls.