In Ireland, a barony (Irish: barúntacht, plural barúntachtaí) is a historical subdivision of a county, analogous to the hundreds into which the counties of England were divided. Baronies were created during the Tudor reconquest of Ireland, replacing the earlier cantreds formed after the original Norman invasion. Some early baronies were later subdivided into half baronies with the same standing as full baronies.

Baronies were mainly cadastral rather than administrative units. They acquired modest local taxation and spending functions in the 19th century before being superseded by the Local Government (Ireland) Act 1898. Subsequent adjustments of county boundaries mean that some baronies now straddle two counties.

The final catalogue of baronies numbered 331, with an average area of 255 km² (98 sq mi; 63,000 acres); therefore, each county was divided, on average, into 10 or 11 baronies.