Background: Although convex-probe endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become a standard procedure for diagnosis of mediastinal disease, including nodal staging for lung cancer, infectious complications are reported occasionally. The aim of this study is to evaluate the rate and risk factors of infectious complications occurring after the procedure. Methods: We retrospectively reviewed 8048 cases of EBUS-TBNA performed at Samsung Medical Center (a 1979-bed referral hospital) between 2009 and 2019. Infectious complications after EBUS-TBNA were defined by clinical features and chest imaging. We randomly selected a control group (2:1) and the risk factors were analyzed using a multivariate logistic regression with backward selection. Results: A total of 33 cases (0.41%) of infectious complication occurred after EBUS-TBNA during the study period; 22 cases (66.7%) with mediastinitis, and 11 (33.3%) with pneumonia. In a multivariate logistic regression analysis including 33 cases of infectious complications and 66 controls, the patients less than 65- year of age (adjusted odds ratio [aOR], 3.63; 95% confidence interval [CI], 1.34-9.80), with a past history of tuberculosis (aOR, 3.61; 95% CI, 1.01-12.89), and cases that underwent transesophageal bronchoscopic ultrasound-guided fine needle aspiration (EUS-B-FNA; aOR, 3.48; 95% CI 1.15-10.52) were associated with significantly higher incidence of infectious complications. Conclusion: EBUS-TBNA rarely causes infectious complications, however a precaution should be considered in young patients with a previous history of tuberculosis or procedure with EUS-B-FNA.