The immediate cause of death of 313 patients who died of lung cancer during 5 years in this center was analyzed. The specific, immediate causes of the 313 deaths were respiratory failure 34. 8%, pneumonia 19. 0%, cachexia 12. 0%, and brain metastasis 8. 3%. Digestive organ disease deaths were 7. 0%(22 patients), being the 5th-ranking immediate cause of death. Of these 22 cases, hepatic insufficiency death by liver metastasis was in 10 out of 22 cases, and gastrointestinal bleeding was in 8 cases. Two patients died of intestinal tract necrosis, but the direct causal relationship between the cause of death and the tumor was unconfirmed from the autopsy result. However, we speculated that an elderly, tumor-bearing condition combined with chemotherapy led to prolonged immobility, a poor nutritional state, and rapid weight loss, which could be influential on the bowel necrosis.