We performed serial pulmonary function test and arterial blood gas analysis at preoperative period and postoperative 1st week in 337 patients who underwent pulmonary resection from May 1988 to April 1992 at Dept. of Thoracic and Cardiovascular Surgery, Seoul adventist hospital. Follow-up study for PFT and ABGA were possible in 30 % of the patients at postoperative 3rd or 4th month. In patient who underwent pneumonectomy, VC was decreased from 57.7% to 46.1%, FVC was decreased from 53.5 % to 41.2 % and MBC also decreased from 68.1% to 49.6 % at postoperative 1st week. But ABGA revealed that POa-, was increased from 87.2 mmHg to 92.7 mmHg, and PCO2 was decreased from 43.2 mmHg to 35.9 mmHg at postoperative 1st week. In patients who underwent lobectomy, VC was decreased from 78.1% to 68.30 %, FVC was decreased from 72.5% to 55.3% and MBC was decreased from 73.5% to 68% at postoperative 1st week.But, ABGA revealed that PO2 was increased from 95.2 mmHg to 97.9 mmHg and PCO2 was decreased from 42.3 mmHg to 39.0 mmHg at postoperative 1st week. The pulmonary function recovered at postoperative 3rd or 4th month and its ratio to preoperative value was 90% in lobectomy cases, but in pneumonectomy cases VC and MBC were recovered 20% and 15 % above the preoperative values. We concluded that resection of atelectasis, destructed lung, open negative and open positive cavity in the pulmonary tuberculosis were beni~t to improve ventilation-perfusion ratio,and pulmonary function was recovered nearly to preoperative level at postoperative 3rd or 4th month.