Acute abdomen due to metastatic primary lung cancer has been reported rarely in the literature, and is associated with a very high operative mortality. Recently, we experienced a patient who presented with a life-threatening complication of small bowel perforation due to the metastasis of primary lung cancer. We reviewed the literature and found that there had been twenty-four cases of lung cancer with small bowel metastasis and perforation since 1961. All patients survived less than 16 weeks and the predominant tumor cell type was squamous cell carcinoma (11/24, 46%). The major site of small bowel perforation was the jejunum (16/24, 67%). In conclusion, lung cancer with metastasis to the small bowel often presents as intestinal perforation and indicates a poor prognosis.