Granvin is a former municipality in the old Hordaland county, Norway. The municipality existed from 1891 until its dissolution in 2020 when it merged with Voss Municipality. The municipality was located in the traditional district of Hardanger. The administrative centre of Granvin was the village of Eide, which is also called "Granvin". About half of the residents of the municipality lived in the municipal centre. The rest lived in the rural valley areas surrounding the Granvin Fjord or the lake Granvinsvatnet in the central part of the municipality.

Prior to its dissolution in 2020, the 211-square-kilometre (81 sq mi) municipality is the 326th largest by area out of the 422 municipalities in Norway. Granvin is the 403rd most populous municipality in Norway with a population of 933. The municipality's population density is 4.6 inhabitants per square kilometre (12/sq mi) and its population has decreased by 4.5% over the last decade.

The parish of Graven was established as a municipality on 1 January 1838 (see formannskapsdistrikt law). This new municipality was very large and it included two annexes to the parish: Ulvik and Eidfjord. On 1 January 1859, "Ulvik" became the main parish, so that Granvin and Eidfjord became annexes to Ulvik, and the name of municipality was changed accordingly.

On 1 May 1891, the municipality of Ulvik was divided into three parts by creating two new municipalities. The western annex (population: 1,331) became the new municipality of Granvin and the southeastern annex (population: 1,018) became the new municipality of Eidfjord. On 1 January 1964, the Lussand-Kvanndal area of Kinsarvik municipality (population: 72) was transferred to Granvin.

On 1 January 2020, the neighboring municipalities of Granvin and Voss were merged into a new large municipality called Voss.

The municipality (originally the parish) is named after the old Granvin farm (Old Norse: Grǫnvin) since the first Granvin Church was built there. The first element is grǫn which means "spruce". The last element is vin which means "meadow" or "pasture". The area is one of the few places in Western Norway that has spruce forests. The name of the parish was spelled as "Graven" before 1858. It was then spelled as "Granvin" from 1858 until 1891. When it became a separate municipality in 1891, the old spelling of "Graven" was used again briefly until 1898. Since 1898 the spelling of "Granvin" has been used.

The coat of arms was granted on 13 May 1988 and it was in use until 1 January 2020 when the municipality was dissolved. The official blazon is "Vert, a fiddle Or in bend sinister" (Norwegian: På grøn grunn ei gul fele, skråstilt venstre-høgre). This means the arms have a green field (background) and the charge is a diagonal hardanger fiddle (Hardingfele), a type of Norwegian folk instrument. The fiddle has a tincture of Or which means it is commonly colored yellow, but if it is made out of metal, then gold is used. The design was chosen to symbolize the rich folk-music traditions in the Hardanger region and it also symbolizes an active and creative community. The fiddle is a simplified representation of the richly decorated Hardanger fiddles. This fiddle, used to play folk dance music, has two sets or layers of four strings and has a very characteristic sound. The lower set of sympathetic strings is not directly touched by the fiddler, but they vibrate when the other strings are played. The arms were designed by Øyvind Kvamme. The municipal flag has the same design as the coat of arms.

The Church of Norway had one parish (sokn) within the municipality of Granvin. It is part of the Hardanger og Voss prosti (deanery) in the Diocese of Bjørgvin.