Sir Nicholas Bagenal built the original manor between 1585 and 1610. The current building dates from the 17th century. Around 1850, the heir to the Bagenal estate, Walter Newton, renovated the house, incorporating parts of the original structure.
In 1989 the house was purchased by Helen and Derek Sheane. The estate was in bad repair, requiring a new roof and extensive work to the windows and floors. 
The manor was redesigned in the c.1850s by British architect Daniel Robertson in the Tudor gothic style. It features ashlar masonry, oriel windows, and fan-vaulted ceilings. The ornate wooden staircase includes several medieval wooden carvings from St Canice's Cathedral in nearby Kilkenny.
- "Dunleckney Manor - Historic houses and castles - Bagenalstown". ireland.com. Retrieved 2 December 2016.
- "Dunleckney Manor - Attractions - Historic Houses and Castles - All Ireland - Republic of Ireland - Carlow - Bagenalstown - Discover Ireland". discoverireland.ie. Retrieved 2 December 2016.
- "Irish Historic Houses Association - House Search". archive.org. 16 May 2016. Archived from the original on 16 May 2016. Retrieved 2 December 2016.
- "Dunleckney House in Bagnelstown Carlow – great visitor attraction !". kehoe.ie. Retrieved 2 December 2016.