PURPOSE: The lung is the second most common site of metastasis from colorectal cancer. Of all patients who undergo a curative resection for colorectal cancer, 10% to 15% will develop lung metastasis. As a hepatic resection of colorectal liver metastases results in improved survival, many reports have suggested that a pulmonary resection of a colorectal lung metastasis would also improve survival. The aim of this study was to analyze the postoperative outcomes of and the prognostic factors for a surgical resection of a lung metastasis. METHODS: Between August 1997 and March 2006, 27 patients underwent surgical resections for colorectal lung metastases at Seoul St. Mary's hospital. A retrospective review of patients' characteristics and various tumor factors was performed. RESULTS: The mean interval between colorectal resection and lung metastasis was 24.0 +/- 15.1 months. The overall 3- and 5-year survival rates were 76.5% and 22.2%, respectively. The mean follow-up after pulmonary resection was 39.5 +/- 21.6 months (range, 3.3 to 115 months). Except for the existence of hilar-lymph-node metastasis (P < 0.001), no risk factors that we studied were statistically significant. Two patients had hilar-lymph-node metastasis. They survived for only for 3.3- and 11.6-months, respectively. CONCLUSION: In our study, we found that a pulmonary resection for metastases from colorectal cancer may improve survival in selected patients.