The Bosnia Vilayet (Serbo-Croatian: Bosanski vilajet/Vilajet Bosna) was a first-level administrative division (vilayet) of the Ottoman Empire, mostly comprising the territory of the present-day state of Bosnia and Herzegovina, with minor parts of modern Montenegro.

In the late 19th century it reportedly had an area of 46,000 square kilometres (17,900 sq mi).

[3] It effectively ceased to exist as an Ottoman province after the Austro-Hungarian campaign in Bosnia and Herzegovina in 1878, although it formally existed for thirty more years until 1908, despite being governed by Austria-Hungary.

This excluded Old Herzegovina, which was ceded to the Principality of Montenegro in 1878.

In 1908, during the Bosnian Crisis, Austria-Hungary formally annexed it into its own territory.