The Bosnia Vilayet was a first-level administrative division (vilayet) of the Ottoman Empire, mostly comprising the territory of the present-day state of Bosnia and Herzegovina. It bordered Kosovo Vilayet to the south. Before the administrative reform in 1867, it was called the Bosnia Eyalet. In the late 19th century it reportedly had an area of 17,900 square miles (46,000km2).
It effectively ceased to exist as an Ottoman province after the Austro-Hungarian occupation of Bosnia and Herzegovina in 1878, although it formally existed thirty more years until 1908 despite being governed by Austria-Hungary. In 1908 Austria-Hungary formally annexed it into its own territory.