Postoperative pneumonia is the most common complication in patients after lung resection for non-small cell lung cancer (NSCLC). The tolerable incidence of this complication ranges from 5 to 8 %. The aim of this study was to evaluate the influence of initial risk factors on the incidence of postoperative pneumonia in patients undergoing lung resection for NSCLC. A retrospective cohort study was conducted at the University Hospital Ostrava between January 1, 2016, and December 31, 2022. All adult patients who underwent pulmonary lobectomy for primary NSCLC during the study period were included in the study. A total of 350 patients were included in the study. The incidence of postoperative pneumonia was 10.9%. Analysis of baseline risk factors did not show a statistically significant association with the incidence of this complication. The only statistically significant finding was a longer hospital stay in patients with postoperative pneumonia. The risk of postoperative pneumonia in patients undergoing lung resection for non-small cell lung cancer cannot be clearly explained by the initial risk factors examined alone. The complex nature of this risk also requires a comprehensive approach to prevention, including both patient-centred measures and improved postoperative care.