Coordinates: 54°14′17″N 6°09′40″W / 54.238°N 6.161°W / 54.238; -6.161

Rathfriland (from Irish: Ráth Fraoileann, meaning "ringfort of Fraoile") is a village in County Down, Northern Ireland. It is a hilltop Plantation of Ulster settlement between the Mourne Mountains, Slieve Croob and Banbridge. It had a population of 2,079 people recorded in the 2001 Census.

In older English documents, the village's name was usually spelt Rathfylan or Rathfrilan. It was once the capital of the Magennis family. The ruins (south gable 30 ft x 25 ft) of an old castle may still be seen on the hill upon which Rathfriland sits. It was a square building of 3-4 storeys with a stone barrel vault at the ground floor to lessen the risk of fire. The castle was once much bigger but most of it was pulled-down by Mr William Hawkins of London, the first Protestant proprietor there after the rebellion of 1641, and the rest destroyed by General Ireton on Oliver Cromwell's orders. The stones were used to build the Town Inn (which still stands on the corner of The Square & Newry Street) and other houses in the village. In 1760 the Market House, which dominates the main square, was built for the linen market by Miss Theodosia McGill. An old map of 1776 prepared for the Meade Estate shows streets, lanes, tenements and gardens forming the early village.