Odda is a former municipality in the old Hordaland county, Norway. The municipality existed from 1913 until its dissolution in 2020 when it was merged into Ullensvang Municipality. It was located in southeastern Hordaland county, surrounding the southern end of the Sørfjorden. The administrative centre was the town of Odda, which was also the main commercial and economic centre of the entire Hardanger region. Other villages in the municipality included Botnen, Eitrheim, Håra, Røldal, Seljestad, Skare, and Tyssedal.

Prior to its dissolution in 2020, the 1,616-square-kilometre (624 sq mi) municipality was the 42nd largest by area out of the 422 municipalities in Norway. Odda is the 150th most populous municipality in Norway with a population of 7,025. The municipality's population density is 4.8 inhabitants per square kilometre (12/sq mi) and its population has decreased by 1.8% over the last decade.

In 1927, Erling Johnson, working at Odda Smelteverk, invented a process to produce three-component, NPK fertilizers. This process is now known as the Odda process.

The municipality of Odda was established on 1 July 1913 when the southern district of Ullensvang was separated out to form its own municipality. Initially, Odda had 3,077 residents. During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee. On 1 January 1964, the neighboring municipality of Røldal (population: 676) was merged into Odda, bringing the total population of the new municipality to 10,163 residents.

On 1 January 2020, the three neighboring municipalities of Jondal, Odda, and Ullensvang were merged. The new municipality is called Ullensvang and its administrative centre is the town of Odda.