Dunleer is a town and townland situated in County Louth, Ireland. It lies midway between Dundalk and Drogheda at the junction of the R132, R169, and R170 regional roads. The settlement serves as the principal town in the former Barony of Ferrard and occupies a civil parish of the same name within the Roman Catholic Archdiocese of Armagh.

The area features ties to an early sixth-century Christian monastery founded by St. Furudran and St. Baothan, which was burned in 1148 before Norman settlement. Records reference the ville of Dún Leire in 1227, with a Market Town Charter granted in 1252. It later received enhanced charters from King Charles II in 1671 and became Ireland's last municipal corporation in 1678.

The town retains historical industrial sites including Glebe Mill, which produces stone-ground flour, and the site of a former flax mill now housing Glen Dimplex. Community landmarks include St. Brigid's Roman Catholic church, a Church of Ireland church, and the Market House, which reopened in 2014 as a civic centre managed by the Dunleer Community Development Board.

Cultural life includes the Dunleer Tidy Towns committee, which won All-Ireland awards in 2017. The town hosts Lann Léire GFC and the Dunleer Athletic Club, which organizes the annual Rás na hÉireann International Cross Country races. Educational facilities comprise three national schools under local parish trusteeship and Scoil Ui Mhuiri Post Primary, which opened a significant extension in 2020.

As of the 2022 census, the population was 2,143, having grown from 1,104 in 1991. The economy benefits from domestic appliance manufacturing and its role as a commuter town for Dublin, Drogheda, and Dundalk. Transport access includes the M1 motorway with three interchanges, Bus Éireann routes, and a disused railway station that closed in 1984.