Background: Pulmonary hamartomas are the most common form of pulmonary benign tumors, and they occur in approximately $2{sim}5%$ of all pulmonary neoplasm. However, only a few reports have been published on the clinical characteristics of pulmonary hamartoma in Korea. Material and Method: The charts, X-rays and pathological specimens of 37 pulmonary hamartoma patients who were diagnosed by a pathological examination from January of 2000 to May of 2005 at the Catholic Medical Center were retrospectively reviewed. Result: The peak incidence of the tumor occurred in the seventh decade of life (32.4%), There were 23 men (62.6%) and 14 women (37.8%), with mean age of 55.6 years. Twenty-six patients (70.3%) were asymptomatic and 11 patients (29.7%) had symptoms. A total of 29 tumors (78.4%) were parenchymal, and 8 (21.6%) were endobronchial. Twenty cases (54.1%) were in the right lung and 17 cases (45.9%) were in the left lung. The right lower lobe was most commonly involved. Thirty-two (86.5%) hamartomas were diagnosed by surgical resection, 4 cases (10.8%) were diagnosed by bronchoscopic biopsy and 1 case (2.7%) was diagnosed by a fine needle aspiration biopsy. Thirty-four hamartomas (91.9%) were managed by surgical resection without complication. No recurrence or malignant changes were seen during the follow up period. Conclusion: Pulmonary hamartomas are most common in males during their fifth to seventh decade and they more commonly involve the right lung. No recurrence or malignant changes were seen during the follow up period.