Rathdowney or Rathdowny (Irish: Ráth Domhnaigh, meaning 'ringfort of the church')[2] is a town in southwest County Laois, Ireland.

It lies some 32 km southwest of Portlaoise in the Irish Midlands, at the point where the R433 regional road from Abbeyleix to Templemore is crossed by the R435 from Borris-in-Ossory to Johnstown.

A half mile southeast of Rathdowney, there stood until 1836, the ruins of a castle called Rathpiper, which most probably took its name from "Pipard", a descendant of Adam de Hereford.

[3] This locality of "Pyperath" within Rathdowny parish appears to have been a royal site associated with the medieval Mac Giolla Phádraig dynasty, as documents relating to meeting there in 1558 show.

Queen Victoria passed through Rathdowney during her first visit to Ireland in 1849 and in a letter to her maternal sibling Princess Feodora of Leiningen about the visit to Ireland she described passing through a town assumed to be Rathdowney by historians as "a quaint village, surrounded by hills" and went on to describe it as "an idyllic small town".