Dundrum (Dún Droma in Irish) is a town in south Dublin, Republic of Ireland, now essentially part of greater Dublin city. The original village clustered around Dundrum Castle (now in ruins), which was built in the 13th century as part of the defences around Dublin. The village remained small until the 19th century when it expanded greatly, particularly after the arrival of the Dublin and South Eastern Railway (DSER) in the 1850s.

The Luas tram system passes through the town, with the "William Dargan Bridge", a large cable-stayed bridge at Taney Cross near the town centre, being one of the bigger engineering structures on the line. The route was originally a railway line opened by the DSER. Shut in the 1950s, the alignment was preserved intact for several decades.

The small Mulvey Park lies to the north.

In 1971, Dundrum was one of the earliest places in Ireland to open a shopping centre (the first being Stillorgan). A much bigger shopping centre opened just south of the village on March 3rd, 2005. It is known as Dundrum Town Centre and is claimed to be the biggest shopping centre in Europe. The old shopping centre is to be demolished and the site redeveloped.

See also: List of towns in the Republic of Ireland