Kilkenny (Irish: Cill Chainnigh [ˌciːl̠ʲ ˈxan̠ʲiː], meaning 'church of Cainnech') is a city in County Kilkenny, Ireland. It is located in the South-East Region and in the province of Leinster. It is built on both banks of the River Nore. The 2016 census gave the population of Kilkenny as 26,512.

Kilkenny is a tourist destination, and its environs include historic buildings such as Kilkenny Castle, St Canice's Cathedral and round tower, Rothe House, Shee Alms House, Black Abbey, St. Mary's Cathedral, Kilkenny Town Hall, St. Francis Abbey, Grace's Castle, and St. John's Priory. Kilkenny is also known for its craft and design workshops, the Watergate Theatre, public gardens and museums. Annual events include Kilkenny Arts Festival, the Cat Laughs comedy festival and music at the Kilkenny Roots Festival.

Kilkenny began with an early 6th-century ecclesiastical foundation within the Kingdom of Ossory. Following the 12th-century Norman invasion of Ireland, Kilkenny Castle and a series of walls were built to protect the burghers of what became a Norman merchant town. William Marshall, Lord of Leinster, gave Kilkenny a charter as a town in 1207. By the late 13th century, Kilkenny was under Hiberno-Norman control. The Statutes of Kilkenny, passed at Kilkenny in 1367, aimed to curb the decline of the Hiberno-Norman Lordship of Ireland. In 1609, King James I of England granted Kilkenny a Royal Charter, giving it the status of a city. Following the Irish Rebellion of 1641, the Irish Catholic Confederation, also known as the "Confederation of Kilkenny", was based in Kilkenny and lasted until the Cromwellian conquest of Ireland in 1649. From 1840 onwards, Kilkenny has not been administered as a city under local government law, but the Local Government Reform Act 2014 provides for "the continued use of the description city".

Kilkenny was a brewing centre from the late 17th century, and still houses a number of breweries. The Heritage Council offices are at Church Lane in the former Bishop's Palace. The seat of the Roman Catholic Bishop of Ossory is at St Mary's Cathedral and the Church of Ireland Bishop of Cashel and Ossory is at St Canice's Cathedral.