PURPOSE: This study was undertaken to determine the preoperative predictors of mortality and morbidity after lung cancer resection. METHOD: During the period from October 1, 1995 to August 31, 1996, a prospective study was conducted in 92 lung resection candidates diagnosed as lung cancer. For preoperative predictors of nonpulmonary factors, we considered age, sex, weight loss, hematocrit, serum albumin, EKG and concomitant illness, and f or those of pulmonary factors, smoking history, presence of pneumonia, dyspnea scale(1 to 4), arterial blood gas analysis with room air breathing, routine pulmonary function test. And predicted postoperative(ppo) pulmonary factors such as ppo-FEV1, ppo-diffusing capacity(DLco), predicted postoperative product(PPP) of ppo-FEV1 % x ppo-DLco% and ppo-maximal O2 uptake(VO2max) were also considered. RESULTS: There were 78 men and 14 women with a median age of 62 years(range 42 to 82) and a mean FEV1 of 2.37+/-0.06L. Twenty nine patients had a decreased FEV1 less than 2.0L. Pneumonectomy was performed in 26 patients, bilobectomy in 12, lobectomy in 54. Pulmonary complications developed in 10 patients, cardiac complications in 9, other complications(empyema, air leak, bleeding) in 11, and 16 patients were managed in intensive care unit for more than 48hours. Three patients died within 30 days after operation. The ppo-O2max was less than 10ml/kg/min in these three patients, but its statistical significance could not be determined due to small number of patients. In multivariate analysis, the predictor related to postoperative death was weight loss (p<0.05), and as for pulmonary complications, weight loss, dyspnea scale, ppo-DLco and extent of resection(p<0.05). CONCLUSIONS: Based on this study, preoperative nonpulmonary factors such as weight loss and dyspnea scale are more important than the pulmonary factors in the prediction of postoperative mortality and/or morbodity in lung resection candidates, but exercise pulmonary fuction test may be useful. Our study suggests that ppo-VO2max value less than 10ml/kg/min is associated with death after lung cancer resection but further studies are needed to validate this result.