BACKGROUND We aimed to investigate the impact of intraoperative blood loss on postoperative pulmonary complications in patients who underwent video-assisted thoracoscopic lobectomy for nonsmall cell lung cancer. METHODS Data of a total of 409 patients (227 males, 182 females; median age: 62 years; range, 20 to 86 years) who underwent lung resection for Stage I-IIIa non-small cell lung cancer in our clinic between July 2017 and April 2018 were retrospectively analyzed. The receiver operating characteristic analysis was used to confirm the threshold value of intraoperative blood loss for the prediction of postoperative pulmonary complications. Propensity score matching was performed to compare between high-intraoperative blood loss and low-intraoperative blood loss groups. A post-matching conditional logistic regression was conducted to determine the independent risk factors for postoperative pulmonary complications. RESULTS Of the patients, 86 (21.03%) developed postoperative pulmonary complications. In the propensity score matching analysis, intraoperative blood loss was shown to be a predictive factor of postoperative pulmonary complications (3.992; 95% confidence interval [CI]: 1.54-10.35; p=0.004). The rate of postoperative pulmonary complications in high-intraoperative blood loss group was significantly higher than that the low-intraoperative blood loss group (37.5% vs. 13.9%, respectively; p=0.003). The postoperative length of stay and duration of postoperative antibiotic use were significantly prolonged in the high-intraoperative blood loss group. CONCLUSIONS Intraoperative blood loss serves as a significant risk factor for postoperative pulmonary complications after lung resection for non-small cell lung cancer. Surgeons should strive to reduce intraoperative blood loss for better surgical outcomes.