Tjølling is a former municipality in Vestfold county, Norway. The 70-square-kilometre (27 sq mi) municipality existed from 1838 until its dissolution in 1988. The area is now part of Larvik Municipality. The administrative centre was the village of Tjøllingvollen. Other villages in Tjølling included Hem, Rekkevik, and Ula.

The parish of Tjølling was established as a municipality on 1 January 1838 (see formannskapsdistrikt law). On 1 January 1891, an area of Tjølling municipality (population: 11) was transferred to the neighboring Hedrum municipality. On 1 January 1988, the municipality was dissolved as part of a major municipality merger which consolidated the municipalities of Brunlanes (population: 8,138), Hedrum (population: 10,449), and Tjølling (population: 7,878) with the towns of Larvik (population: 8,045) and Stavern (population: 2,538) to create a new, much larger Larvik Municipality with a population of 37,048 people.

The municipality (originally the parish) is named after an old name for the area (Old Norse: Þjóðarlyng) since the first Tjølling Church was built there. The first element is the genitive case of the word þjóð which means "crowd of people" or "assembly". This is likely because the site was apparently the location of a Thing for the district long before the introduction of Christianity. The last element is lyng which means "heather".

The coat of arms was granted on 7 May 1971. The official blazon is "Azure, two longships argent in pale" (Norwegian: På blå bunn to sølv langskip). This means the arms have a blue field (background) and the charge is a set of two longships, one above the other. The pair of longships has a tincture of argent which means it is commonly colored white, but if it is made out of metal, then silver is used. The two Viking ships in the arms and refer to the long history of the area. The arms were designed by Hallvard Trætteberg. The municipal flag has the same design as the coat of arms.

Historic numbers show that Tjøllings population grew from the early 19th century until the municipal merger in 1988.

Historical population

Year Pop. ±% p.a. 1845 2,290 —     1855 2,509 +0.92% 1865 3,012 +1.84% 1875 3,343 +1.05% 1891 3,620 +0.50% 1900 3,639 +0.06% 1910 3,532 −0.30% 1920 4,035 +1.34%	Year Pop. ±% p.a. 1930 4,307 +0.65% 1946 4,575 +0.38% 1951 4,911 +1.43% 1960 5,673 +1.62% 1970 6,772 +1.79% 1980 7,412 +0.91% 1988 7,878 +0.77%
Source: Statistics Norway and Norwegian Historical Data Centre

Tjølling is the site of one of the oldest Viking Age settlements within Scandinavia. Kaupang was a big trading centre for the Vikings. Kaupang is considered to be Norway's first city, being mentioned by Ohthere of Hålogaland when he visited Alfred the great around year 890. There have been several earlier archaeological surveys and excavations at Kaupang. In 1867, antiquarian Nicolay Nicolaysen mapped one of the grave-fields around the former town and excavated 79 grave mounds. He uncovered a cremation cemetery, largely dated to the 10th century. Charlotte Blindheim (1917-2005) started excavating in 1947 and completed her last publication in 1999. In 1997, Dagfinn Skre and his associates from the University of Oslo undertook a new program of work at Kaupang followed by a large excavation that ran over three years, from 2000 till 2002. Most recently it has been the site of post-excavation work conducted by the University of Oslo.

Tjøllingvollen (or simply Vollen) is located at the highest part of the outer raet. The village is the administrative centre of Tjølling. The village is a well developed rural area, with a grocery store, kindergarten, post office, primary and secondary school, health and elderly institutions, among others. During the 1960s and 1970s, the residential area of Vollen was expanded and this has continued into the 21st century.

Tjølling Church (Tjølling kirke) was originally constructed as a medieval stone church in the 12th century. The church was hit by a fire in 1360 and was then rebuilt. An earthquake damaged the church in the 1750s. It has been speculated that it was the 1755 Lisbon earthquake, but it's more plausible that it was an earthquake in Kattegat in 1759 that caused the damages. It was rebuilt from 1762 to 1767 as a Romanesque church with interiors from different eras. The restoration in 1860 gave Tjølling church its present appearance.

While it existed, this municipality was responsible for primary education (through 10th grade), outpatient health services, senior citizen services, unemployment, social services, zoning, economic development, and municipal roads. During its existence, this municipality was governed by a municipal council of directly elected representatives. The mayor was indirectly elected by a vote of the municipal council.

The municipal council (Kommunestyre) of Tjølling was made up of representatives that were elected to four year terms. The tables below show the historical composition of the council by political party.

The mayors (Norwegian: ordfører) of Tjølling:

Tjølling includes the 69.5 square kilometres (26.8 sq mi) area between the river Numedalslågen and Sandefjordsfjorden, south of the European route E18 highway.

There's some agriculture and numerous quarries excavating of larvikite in Tjølling. The biggest quarry is Klåstad, which extracts a type of larvikite called Mørk Labrador (English: Dark Labrador).

Tjølling has a long coastline with many fine beaches and coves. Tjølling is also known as a popular cottage area, as well as a popular holiday area. The most popular ports are Ula and Kjerringvik. Viksfjord is an idyllic sidefjord to Larviksfjorden, and is located in Tjølling.

Tjodalyng school is a primary and secondary school for Tjølling, with around 520 students and 60 employees. The school was built as a primary school in 1963, and was expanded as a secondary school in 1976.

Tjølling IF was founded in 1888, and is located at Løveskogen Idrettspark. They operate also Tjøllinghallen, which is located in the same area. The club also has artificial turf pitches, a grass pitch, two peach pitches, and a clubhouse. The club has 27 association football teams, where nine of those are women's teams, and 18 are men's teams. They also have 18 children's teams, six youth teams, three adult teams, and 23 coaches. The sports association has other activities as well, like "allis" for kids between 2–7 years old, and activities for former members. There's also Tjøllingmila and Vestfold Maraton, which they arrange.

• List of former municipalities of Norway