Background: Donor/recipient (D/R) size matching is a key requirement in lung transplantation (LT) to achieve proper organ allocation. There are several reports about the size mismatched LT, but their results were contradicted. In this study, we review the outcome of LT according to their D/R size match. Methods: Patients who underwent LT between January 2010 and December 2022, totaling 446, were analyzed. Patients were divided into three groups according to D/R size. The grouping was as follows: Over (n=108, 24.2%) for a >120% D/R ratio, NL (n=314, 70.4%) for a 120% to 80% D/R ratio, and Under (n=23, 5.2%) for a <80% D/R ratio. Their early and long-term outcome were analyzed. Results: Incidence of grade 3 primary graft dysfunction (PGD) at 24 hours and 48 hours were higher in bigger sized D/R ratio (42.6% in Over vs. 35.7% in NL vs. 13.0% in Under, P=0.02 at 24 hours; 36.1% vs. 25.2% vs. 13.0%, P=0.012 at 48 hours). PGD grade 3 at 72 hours also showed higher trend incidence in bigger D/R match (31.5% vs. 20.4% vs. 13.0%, P=0.069). Intensive care unit stay was shorter trend in smaller D/R (13.64±10.98 in Over vs. 11.40±9.59 in NL vs. 8.59±4.98 in Under, P=0.058). The 5year survival was not different among groups (51.7.% vs. 51.9% vs. 54.8% in Over vs. NL vs. Under, P=0.929). Conclusions: Even bigger D/R matched LT showed late recovery during early postoperative period, their long-term result was not different in terms of D/R size ratio.