South Tyrol (German: Südtirol; Italian: Alto Adige; Ladin: Südtirol), officially the Autonomous Province of Bolzano, is an autonomous province in Northern Italy, one of the two that make up the autonomous region of Trentino-Alto Adige/Südtirol. The province is the northernmost of Italy, the second largest, with an area of 7,400 square kilometres (2,857 sq mi) and has a total population of about 534,000 inhabitants as of 2021. Its capital and largest city is Bolzano (German: Bozen; Ladin: Balsan or Bulsan).

According to the 2011 census, 62.3% of the population uses German as their first language (Standard German in the written form and an Austro-Bavarian dialect in the spoken form); 23.4% of the population speaks Italian, mainly in and around the two largest cities (Bolzano, with an Italian-speaking majority, and Meran, with a slight German-speaking majority); 4.1% speaks Ladin, a Rhaeto-Romance language; 10.2% of the population (mainly recent immigrants) speaks another language natively. Of 116 South Tyrolean municipalities, 103 have a German-speaking, eight a Ladin-speaking, and five an Italian-speaking majority. There was large-scale immigration of Italians from the rest of Italy to Bolzano and its surroundings after 1918.

The province is granted a considerable level of self-government, consisting of a large range of exclusive legislative and executive powers and a fiscal regime that allows it to retain 90% of revenue, while remaining a net contributor to the national budget. As of 2016, South Tyrol is the wealthiest province in Italy and among the wealthiest in the European Union.

In the wider context of the European Union, the province is one of the three members of the Tyrol–South Tyrol–Trentino Euroregion, which corresponds almost exactly to the historical region of Tyrol. The other members are Tyrol state in Austria, to the north and east, and the Italian Autonomous Province of Trento to the south.