<p> OBJECTIVE: To identify preoperative and intraoperative risks factors for postoperative complications developed in lung resection surgery. METHODS: During 12 months from jan 2015 to dec 2015; 100 patients underwent pulmonary resection and were enrolled to the study. After a clinical interview, patients were evaluated by laboratory, pulmonary function tests and radiography, submitted to a surgical procedure, and were followed during their stay in the ICU and hospital, evaluating postoperatory complications and death. RESULTS: The postoperative rate of complications was 30%: respiratory (16%), infectious (10%), and cardiovascular (4%). Respiratory complications were related to smoking (p < 0.01, RR 2.31), airway obstruction by spirometry (p = 0.01, RR 2.60), presence of anemia (p < 0.01, RR 2.13), and prolonged protrombine time [PT] (p = 0.03, RR 1.77). Infection complications were related to smoking (p < 0.01, RR 2.69), airway obstruction by spirometry (p = 0.01, RR 3.31), presence of anemia (p < 0.01, RR 2.10), and prolonged PT (p = 0.03, RR 2.29). Cardiovascular problems were related with older age (p < 0.01, RR 2.66), cigarette smoking (p < 0.01, RR 4.55), and hypoxemia (p = 0.03, RR 2.43). The postoperative mortality rate was 7.1%. CONCLUSION: A preoperative evaluation can provide a suitable and safe postoperative prediction of complications in patients submitted to lung resection. Patients with COPD, hypoxemic, older, and anemic patients must be classified as high-risk for developing these complications. </p>