The esophageal hiatal hernia is a rare disease in Korea especially in children and infant. We experienced a case of type III esophageal hiatal hernia in 9 months female. She had no specific past history and familial history except recurrent URI and postprandial habitual vomiting. The chest X-ray and Barium swallowing showed herniated stomach in Rt. thoracic cavity and posterior mediastinum. We performed modified Belsey Mark IV procedure with using the 3-0 and 4-0 Pledgeted Ticrons. In operative field, the stomach cardia portion was herniated into the Rt.thoracic cavity and posterior mediastinum with elevation of the esophagogastric junction above the diaphragm. But there was no evidence of short esophagus and combined anomaly. The postoperative courses were uneventful and good without specific complication for about 5 months to this point.