A 73-year-old, previously healthy man presented with nausea, vomiting, diarrhea, dry mouth and febrile sensation 3 hours after eating boiled wild mushrooms. After admission, he showed progressive severe respiratory distress, pancytopenia, azotemia, hypotension, hypoxemia and consolidation of the entire left lung on chest radiography. With a preliminary diagnosis of necrotizing pneumonia, he underwent left pneumonectomy in order to remove all necrotic lung tissue. Lung histology showed extensive hemorrhagic necrosis, massive inflammatory cell infiltration, prominent proliferation of young fibroblasts and the formation of an early-stage hyaline membrane along the alveolar wall. Despite aggressive treatment, including mechanical ventilation, continuous renal replacement therapy and administration of granulocyte colony stimulating factor and broad spectrum antibiotics, he died on hospitalization day 13. Subsequently, the mushroom was identified as Podostroma cornu-damae. This is the first case of a histological evidence of lung involvement by Podostroma cornu-damae poisoning in Korea.