Recent reports on the CT evaluation of patients with diverticulitis of the left colon prompted a retrospective review of the CT findings in six patients with diverticulitis of the cecum and ascending colon. All had pain and tenderness in the right lower quadrant. In each case, CT findings showed regional thickening of the colonic wall, an extraluminal mass involving the cecum and/or ascending colon, haziness and linear strands in adjacent pericolic fat, and thickening of nearby fascial planes. Extraluminal air was noted in four patients, and contrast-filled structures suggesting diverticula were present within the inflammatory masses of two. These results suggest that CT is a useful imaging tool in the diagnosis of right-sided diverticulitis.