Congenital diaphragmatic hernia is associated with a significant mortality, despite intensive treatment. The degree of pulmonary vascular hypoplasia is the main factor affecting mortality. Various features have been considered to determine the prognosis in these infants. In this study a series of 50 consecutive cases of left-sided diaphragmatic hernia has been reviewed. The site of the stomach (abdominal or intrathoracic), demonstrated radiologically and confirmed at operation, has been related to the final outcome (survival or death). An abdominal site is associated with an excellent prognosis (6.2% mortality), while an intrathoracic site is associated with a 58.8% mortality.