90 patients[75 men and 15 women] with the thoracic disease underwent video-assisted thoracic surgery[VATS] during the period March 1992 to February 1993. The thoracic diseases were classified into two groups of spontaneous pneumothorax and general thoracic patients and they were 66 and 24, respectively.The mean size of the tumor resected was 4.3 $pm$ 2.0 cm x 3.3 $pm$ 1.1 cm x 2.7 $pm$ 1.0 cm. The mean time of anesthesia and operation were 90.0 $pm$ 19.9 min and 43.7 $pm$ 13.1 min in spontaneous pneumothorax group and 123.3 $pm$ 40.3 min and 62.8 $pm$ 32.2 min in general thoracic group. The mean period of postoperative chest tube drainage and hospital stay were 5.0$pm$ 5.5 days and 6.6 $pm$ 7.4 days in spontaneous pneumothorax group and 3.5$pm$ 1.6 days and 9.5 $pm$ 6.1 days in general thoracic group. The indications of VATS were 71 pleural disease[78.9%: 66 spontaneous pneumothorax; 3 pleural effusions ; 1 pleural paragonimus westermanii cyst; 1 malignant pleural tumor with metastasis to the lung], 9 mediastinal disease[10.0%: 5 benign neurogenic tumor; 2 pericardial cyst; 1 benign cystic teratoma; 1 undifferentiated carcinoma], 8 pulmonary parenchymal disease[8.9%: 3 infectious disease ; 3 interstitial disease ; 2 malignant tumor ], and 2 traumatic cases of exploration and removal of hematoma[2.2%]. The applicated objectives of VATS were diagnostic[ 7 ], therapeutic[ 67 ] and both[ 16 ] and the performed procedures were pleurodesis[ 66 ], wedge resection of lung[ 59 ], parietal pleurectomy[ 11 ], removal of benign tumor[ 9 ], excision and/or biopsy of tumor[ 4 ], pleural biopsy and aspiration of pleural fluid[ 3 ] and exploration of hemothorax and removal of hematoma in traumatic 2 patients. The complication rate was 24.2%[ 16/66 ] in the spontaneous pneumothorax group and 8.3%[ 2/24 ] in the general thoracic group and so overally 20.0%[ 18/90 ]. The mortality within postoperative 30 days was 2.2%[ 2/90 ], including 1 acute renal failure and 1 respiratory failure due to rapid progression of pneumonia. The conversion rate to open thoracotomy during VATS was 5.6%[ 5/90 ], including 2 immediate postoperative massive air leakage, 1 giant bullae, 1 malignant pleural tumor with metastasis to lung and 1 pulmonary malignancy. The successful cure rate of VATS was 75.8%[ 50/66 ] in the spontaneous pneumothorax group and 76.5%[ 13/17 ] in the general thoracic group and the successful diagnostic rate was 100%[ 7/7 ]. In conclusion, although prospective trials should be progressed to define the precise role of VATS, the VATS carries a low morbidity and mortality and high diagnostic and therapeutic success rate and now can be effectively applicated to the surgical treatment of the extensive thoracic disease.