Boerhaave's syndrome, spontaneous esophageal rupture, is lethal and associated with a 70% survival rate despite emergent surgical management in recent reports. Early diagnosis and management is critical for more favorable outcome. But, it is difficult to diagnose early because of the low incidence and lack of specific symptoms and signs. We experienced 37 year-old male patient with Boerhaave's syndrome who was heavy drinker, and suffered from chronic renal failure. He visited a hospital because of hematemesis and severe back pain. He was transferred to our hospital with a nasogastric tube insertion, which was penetrating the distal esophagus. A radiologic examination revealed that the distal tip was located in the left pleural cavity. It was assumed that the tube had passed through the preexisting perforation site. Operation was not performed emergently due to delay in diagnosis and severe hyperkalemia. The patient was in a septic condition, but had recovered slowly after systemic broad spectrum antibiotic therapy, pleural drainage and intrapleural antibiotic injections. An esophagography revealed no leakage of gastro-grafin on the 14th hospital day, and he later completely recovered from sepsis. (Korean J Gastrointest Endosc 19: 414∼420, 1999)