Aghnatrisk () is a rural townland in County Down, Northern Ireland. It has an area of 252.03 acres (1.02 km<sup>2</sup>). It is situated in the civil parish of Blaris (Iveagh portion) and the historic barony of Iveagh Lower, Upper Half, located 4 miles south-west of Lisburn. It lies within the Lisburn and Castlereagh City Council.