Lenaderg is a small village and townland (of 335 acres) in County Down, Northern Ireland. It sits on the banks of the River Bann, about two miles from Banbridge and a half mile from the village of Lawrencetown. It is situated in the civil parish of Tullylish and the historic barony of Iveagh Lower, Upper Half. In the 2001 Census it had a population of 261 people. Lenaderg is within the District of Banbridge.