Transmesenteric hernia occurs usually in adult patients who had history of an abdominal surgery or blunt abdominal trauma. Congenital mesenteric defect is a relatively common cause of internal hernia in children. However, the report of CT findings of congenital transmesenteric hernia is relatively rare. Thus, we report a case of congenital transmesenteric hernia occurring in a 13-year-old girl with intestinal obstructive symptoms, and include the CT findings.