Cardiopulmonary resuscitation is frequently required for severely depressed congenital diaphragmatic hernia patients. If the exact condition of the patient is not diagnosed prior to delivery, fatal complications such as tension pneumothorax occur often during the resuscitation process. In this case we report the difficulties in diagnosing congenital diaphragmatic hernia and the unusual responses and complications during cardiopulmonary resuscitation. We should know the various methods of management developed over the recent 10 years for these highly stressed patients.