Benign lung tumors have been considered as relatively rare disease, which comprise approximately 8 to 15% of all solitary pulmonary lesions that are detected radiographically. We clinically analized 30 cases of benign lung tumors underwent the operation from Jan. 1970 to Aug.1991 in the department of thoracic and cardiovascular surgery, Catholic University Medical College. We adopted the classification presented by the World Health Organization[WHO], modified from Liebow, and added benign mesothelioma. There were 11 males & 19 females ranging in age from 2 years to 68 years old % the mean age was 38 years old. Of all 30 benign lung tumors, hamartomas [14 cases, 49%] were the most common & followed by hemangiomas [9 cases, 30%], 3 cases of benign mesotheliomas % a case of teratoma, papilloma, arteriovenous malformation and inflammatory pseudotumor. 14 cases of tumors were asymptomatic & were incidentally detected by plane chest x-ray In other cases, chief complaints at admission were coughing, chest discomfort, dyspnea, hemoptysis, and fever. Diagnosis were made by pathological examination; exploratory thoracotomy in 23 patients[76.7%], bronchoscopy in 4 patients and percutaneous needle aspiration biopsy in 3 patients. Precisely, preoperative diagnosis for confirmation of benign lung tumor was made only in 7 cases[23.6%]. Tumors were located on Rt.side[24 cases], especially Rt. middle lobe, and Lt.side[6 cases]. Operation methods were as follows: 21 cases [70%] of lobectomy, 2 cases of segmentectomy, 2 cases of wedge resection, 1 case of pneumonectomy, 1 case of bronchotomy, 2 cases of wedge resection, 1 case of pneumonectomy, 1 case of bronchotomy removal of the endobronchial hamartoma which located at the rt. main stem bronchus and 3 cases of complete resection in benign mesotheliomas. There were no operative death. The post operative complications were developed in 3 cases; post pneumonectomy empyema, wound infection and atelectasis. In conclusion, benign lung tumors must be histologically diagnosed to confirm of benignity and to provide limited resection for preservation of the lung tissue, whenever possible.