Symptomatic gastro-intestinal (GI) metastasis in lung carcinomas is extremely rare and only a few case reports have been published. Here we review all of the cases of lung cancer from January 2003 to April 2005 in a tertiary teaching hospital in Taiwan. A total of six patients (1.77%, 6/339) with primary lung cancer demonstrated symptomatic gastro-intestinal metastasis. Three patients had squamous cell carcinoma, one had adenocarcinoma, and two had small cell carcinoma. Three patients with gastric metastasis were diagnosed via gastro-endoscopy while one with cecal involvement was diagnosed via colon fiberscopy. Two patients with small bowel perforation and intussusception were diagnosed via laparotomy. We presented these rare cases and made a review of the literature.