Case 1, a 9-year-old woman, was admitted to our hospital because of nausea, vomiting, and epigastralgia. Diagnosis of Bochdalek hernia was made by the unusual course of naso-gastric tube. At surgery through the left posterorateral thoracotomy, the herniation of the stomach, small intestine, and colon to the thoracic cavity through the dorsolateral defect of the diaphragm were revealed. Case 2, a 35-year-old man, was admitted to our hospital because of dyspnea. Similar diagnosis was made by the examination of upper G1 series and barium enema, which demonstrated the presence of multiple loops of the small intestine and colon in the left thoracic cavity. Their postoperative courses were uneventful. Most of Bochdalek hernia is observed in infancy, and adolescent or adult case is is rarely reported (approximately 10% of all cases). Since this often misdiagnosed as pleuritis or pulmonary tuberculosis, a cautious examination is necessary for the establishment of the correct diagnosis.