is municipality in Agder county, Norway. It is located in the traditional district of Sørlandet. The administrative center is the town of Tvedestrand. There are many villages in the municipality including Dypvåg, Fiane, Gjeving, Gødderstad, Grønland, Kilen, Klåholmen, Krokvåg, Laget, Lyngør, Nesgrenda, Østerå, Sagesund, Sandvika, and Songe.
The town of Tvedestrand has a white-painted town center with irregular streets climbing steep hills around the harbor. The natural environment of the area makes it a tourist destination. The municipality includes numerous islands, which makes it popular in the summer for boaters. The number of people in the municipality practically doubles in the summer, due to vacationers. There are approximately 1,700 summer cottages ("hytter") around the fjord and coastal areas. Tvedestrand has over 2,000 buildings that are more than 100 years old.
The municipality is the 298th largest by area out of the 356 municipalities in Norway. Tvedestrand is the 155th most populous municipality in Norway with a population of 6,115. The municipality's population density is and its population has increased by 1.6% over the previous 10-year period.
The town of Tvedestrand was established as a municipality on 1 January 1838 (see formannskapsdistrikt law). During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee. On 1 January 1960, the rural municipalities of Dypvåg (population: 1,805) and Holt (population: 3,759) were merged with the town of Tvedestrand (population: 868) to form a new municipality named Tvedestrand.
On 1 January 1962, the Strengereid area (population: 375) of Tvedestrand was transferred to neighboring Moland municipality. Then on 1 January 1964, the Holtegården area (population: 5) was transferred from Moland to Tvedestrand. The uninhabited Folevatnet area in Tvedestrand was transferred to the municipality of Risør on 1 January 1984.
The town and municipality is named after the old Tveite farm (Þveitar) since that is the location of the present town of Tvedestrand.