The collapsed Portal Tomb of Killoneery (or Killonerry) is situated on a low, irregular hill, approximately 10 meters in diameter, within a pasture in the townland of Killonerry (in Irish, Cill Ó Neire) in the far west of County Kilkenny, Ireland. It is located about 100 meters west of the Lingaun River (An Loinneán), a tributary of the River Suir, which forms the border with County Tipperary at this point.
The long, displaced capstone measures 3.8 meters in length, 2.6 meters in width, and is up to 1.6 meters thick. It rests diagonally on the collapsed chamber. The portal stones were originally 1.4 meters high, while the end stone has been fragmented. Cairn material is present underneath the capstone and the doorstone, and the chamber is filled with stones.
Nearby lies the Passage Tomb of Knockroe.