Morgagni hernia is a rare congenital disorder, which is usually asymptomatic, but may cause respiratory or gastrointestinal symptoms. We reviewed the clinical findings of three patients with a Morgagni hernia, diagnosed and treated in our department between 1997 and 2000. The Morgagni hernia caused various symptoms in all three patients and surgery was performed via posterolateral thoracotomy in two, and via laparatomy in one. The hernial defect was closed by primary suturing in two patients and by synthetic mesh in one. All three patients had an uneventful postoperative recovery. We believe that the transthoracic approach is an effective way of repairing Morgagni hernia.