BACKGROUND: we have evaluated the association of age, smoking, type of anesthesia, type of operation, duration of surgery, previous history of chronic pulmonary diseases with postoperative pulmonary complications and identified which parameter of preoperative spirometry was a predictor of postoperative pulmonary complications. METHOD: In 270 patients older than 60 years, the postoperative pulmonary complications were evaluated according to age, smoking, type of anesthesia, type of operation, duration of surgery, previous history of chronic pulmonary diseases and the parameters of preoperative spirometry were analyzed. RESULTS: The postoperative pulmonary complications rates were significant higher among patients older than 70 years, and among those with previous chronic pulmonary diseases or their smoking history. The pulmonary complications were increased among patients with general anesthesia or duration of surgery more than 2 hours. The pulmonary complications rates did not differ according to sex, type of operation. The patients with hypercarbia(PaCO2> 45mmHg) have more increased postoperative complications. The preoperative FEVl less than 1 liter, FVC, MMEFR