County Tipperary (Irish: Contae Thiobraid Árann) is a county in Ireland. It is in the province of Munster and the Southern Region. The county is named after the town of Tipperary, and was established in the early 13th century, shortly after the Norman invasion of Ireland. It is Ireland's largest inland county and shares a border with eight counties, more than any other. The population of the county was 167,895 at the 2022 census. The largest towns are Clonmel, Nenagh and Thurles.

Tipperary County Council is the local authority for the county. In 1838, County Tipperary was divided into two ridings, North and South. From 1899 until 2014, they had their own county councils. They were unified under the Local Government Reform Act 2014, which came into effect following the 2014 local elections on 3 June 2014.

Tipperary is the sixth-largest of the 32 counties by area and the 12th largest by population. It is the third-largest of Munster's six counties by both size and population. It is also the largest landlocked county in Ireland.

Tipperary is bounded (clockwise) by counties Offaly, Laois, Kilkenny, Waterford, Cork, Limerick, Clare and Galway. Its eight neighbours are the most of any county on the island.

The region is part of the central plain of Ireland, but the diverse terrain contains several mountain ranges: the Knockmealdown, the Galtee, the Arra Hills and the Silvermine Mountains. Most of the county is drained by the River Suir; the north-western part by tributaries of the River Shannon; the eastern part by the River Nore; the south-western corner by the Munster Blackwater. No part of the county touches the coast. The centre is known as 'the Golden Vale', a rich pastoral stretch of land in the Suir basin which extends into counties Limerick and Cork. At 917 m, Galtymore is the highest point.

The Devil's Bit is a part of the Slieve Bloom range. The River Shannon flows along the northwest border with counties Limerick, Galway and Clare. The River Suir rises at the Devil's Bit and flows into the sea east of Waterford.

There are 12 historic baronies in County Tipperary: Clanwilliam, Eliogarty, Iffa and Offa East, Iffa and Offa West, Ikerrin, Kilnamanagh Lower, Kilnamanagh Upper, Middle Third, Ormond Lower, Ormond Upper, Owney and Arra and Slievardagh.

Parishes were delineated after the Down Survey as an intermediate subdivision, with multiple townlands per parish and multiple parishes per barony. The civil parishes had some use in local taxation and were included on the nineteenth century maps of the Ordnance Survey of Ireland. For poor law purposes, district electoral divisions replaced the civil parishes in the mid-nineteenth century. There are 199 civil parishes in the county. Townlands are the smallest officially defined geographical divisions in Ireland; there are 3,159 townlands in the county.