New Ross (Irish: Ros Mhic Thriúin, formerly Ros Mhic Treoin) is a town located in southwest County Wexford, in the southeast of Ireland. In 2006 it had a population of 7,709 people, making it the fourth largest town in the county after Wexford, Gorey and Enniscorthy.

The port town of New Ross dates from the Middle Ages. The earliest settlement in this area dates back to the 6th century when St. Abban of Magheranoidhe founded a monastery in what is now the Irishtown. The original earthen banked circular enclosure of his monastery was visible around the graveyard until about 10 years ago when it was unceremoniously removed by the council. It has been replaced by a concrete wall and steel fence. Its name, Ros, was shortened from Ros Mhic Treoin, or the Wood of the Son of Treon.

Until the creation of ships too large to reach the port, in the nineteenth century, New Ross was a prosperous port town. However, the river is too shallow to allow passage of large ships and the port gradually went into decline. The town continued to be a prosperous market town for the rich agricultural hinterland, but suffered from severe recession throughout the 1970s, 1980s, and early part of the 1990s. As of now there is a small amount of industry in the area and most businesses centre around services and retail although the local retail trade is under pressure from a number of larger retail outlets like Tesco, Lidl and Aldi which attract business away from the centre of town to the outskirts. However the town is so small that many of these shops are within walking distance of one another.

Latterly it has benefited from professionals making their homes in the town who work in Waterford, about 25 km (16 mi) away. There is also a strong international community, mainly eastern European, in New Ross, associated with the transport and manufacturing industries. There are two Polish shops and one Lithuanian. A degree of tourism associated with The Dunbrody replica famine ship and the connection with the Kennedy family also benefits the town.