James M. Cox Dayton International Airport (IATA: DAY, ICAO: KDAY), also referred to as simply Dayton International Airport, is a public airport located 9 miles (14 km) north of the city of Dayton in Montgomery County, Ohio, USA.

It was founded in 1936 when the city purchased the original private airstrips from a corporation. The airport is named after James M. Cox, a former governor of Ohio, Democratic presidential nominee, and publisher of the Dayton Daily News.

Dayton International currently serves as the headquarters for US Airways Express carrier PSA Airlines. Dayton has emerged as an attractive destination for more airlines and more airline destinations in recent years, notably from low fare carriers. AirTran Airways and Frontier Airlines have emerged as significant competitors at Dayton to the "legacy" carriers. On August 12, 2012, Southwest Airlines began serving Dayton International Airport with service to Denver International Airport. This change is a major boost to the airport and is expected to increase passenger traffic at the airport by at least 15 percent