The nearest airport is ITM - Osaka Intl, located 54.8 km north of Kōyaguchi.
Other airports nearby include SHM - Nanki-shirahama Nanki Shirahama (72.8 km south), TKS - Tokushima (88.9 km west), TAK - Takamatsu (141.6 km west), OKJ - Okayama (163.6 km west),