A case of late presentation of left congenital diaphragmatic hernia (CDH) in a boy of 9 months is reported. A chest X-ray taken after (premature) birth gave normal results; hence this type of CDH is called "acquired". Not being associated with pulmonary hypoplasia, this condition is difficult to diagnose. The patient presented as an emergency and the initial diagnosis was tension pneumothorax. This resulted in the insertion of a chest tube, fortunately without damage to the herniated stomach and spleen. Doubling upward of the tip of the nasogastric tube led to the correct diagnosis. After successful repair of the diaphragm the child made a full recovery.