Only 5% of all cases of intussusceptions occur in adults. Intussusception complicating colonoscopy is an extremely rare event. Herein, we present a case of a 58-year-old man who developed ileocolic intussusception after a colonoscopy during which an adenomatous polyp was discovered in the terminal ileum. Eight hours after colonoscopy, the patient developed diffuse abdominal pain associated with vomiting and bloody diarrhea. A contrast-enhanced abdominal computed tomography scan revealed features of mechanical intestinal obstruction and a round soft tissue mass inside the right colon, followed by the wall of the intussusceptum. Emergency laparotomy revealed extended ileocecal intussusception with the polyp incarcerated by the ileocecal valve. A typical right hemicolectomy was performed, and the patient had an uneventful recovery. Histologic examination of the surgical specimen revealed an inflammatory fibroid polyp. Ileocolic intussusception due to an ileal polyp may be precipitated by colonoscopy and should be included in the differential diagnosis of acute abdomen after colonoscopy.