Deatnu (Northern Sami) or Tana (Norwegian) is a municipality in Finnmark county, Norway. The administrative centre of the municipality is the village of Tana bru. Among the other villages in the municipality are Austertana, Bonakas, Polmak, Rustefjelbma, and Skiippagurra.

The 4,051-square-kilometre (1,564 sq mi) municipality is the 5th largest by area out of the 357 municipalities in Norway. Deanu-Tana is the 239th most populous municipality in Norway with a population of 2,807. The municipality's population density is 0.7 inhabitants per square kilometre (1.8/sq mi) and its population has decreased by 2.6% over the previous 10-year period.

On 1 January 1864, the large Lebesby Municipality was divided into two. The eastern part (population: 1,388) became the new Tane Municipality and the rest remained as Lebesby. Initially, Tana Municipality included all the land on both sides surrounding the Tanafjorden and the Tana River.

On 1 January 1914, the municipality of Tana was divided into three parts. The southern part (population: 1,426) remained as (a smaller) Tana Municipality. The northern part of the municipality was divided by the Tanafjorden with the western side becoming Gamvik Municipality (population: 1,374) and the eastern side becoming Berlevåg Municipality (population: 784). On 1 January 1964, the neighboring Polmak Municipality (population: 1,072) was merged into Tana. (Polmak was originally part of Nesseby Municipality before 1 January 1903 when it became a separate municipality.)

Tana Municipality marks the furthest Soviet advance into Nazi-occupied Norway.

On 1 January 2020, the municipality became part of the newly formed Troms og Finnmark county. Previously, it had been part of the old Finnmark county. On 1 January 2024, the Troms og Finnmark county was divided and the municipality once again became part of Finnmark county.

The municipality (originally the parish) was originally named Tanen, a Norwegianized form of the Northern Sami name for the area, Deanu. The Sami name is identical to the genitive case of Sami word deatnu which means "great river" or "large river", referring to the main river (Tana River) which runs through the municipality. Historically, the name of the municiaplity was spelled Tanen. On 3 November 1917, a royal resolution changed the spelling of the name of the municipality to Tana.

On 1 September 1992, the name of the municipality was changed to "Deatnu-Tana" to symbolize the two official languages in the municipality. Then in 2005, the name was again changed such that either Deatnu or Tana can be used. The Sami language name spelling changes depending on how it is used. It is called Deatnu when it is spelled alone, but it is Deanu gielda when using the Sami language equivalent to "Deanu municipality".

The coat of arms was granted on 11 May 1984. The official blazon is "Gules, three boats Or in pale" (Norwegian: I rødt tre gule båter). This means the arms have a red field (background) and the charge is three riverboats. The riverboat 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 red and yellow colors in the arms were chosen to mimic the Norwegian national arms. The three riverboats were chosen because boats like this have been used in the area for centuries. There are three boats to symbolize the three ethnic groups in the border municipality: the Sámi, Kvens, and Norwegians. The arms were designed by Arvid Sveen.

In 2013, 29% of the work force was employed in retail, hotels/restaurants and finance; 23% in the healthcare industry and the social sector; 16% in the Secondary sector of the economy; 11% in the primary sector; 9% worked in the education sector; the work force totaled 1,401.

The most important [economic] resources are farmland and [coastal areas, mountains and forests or] utmark; the use of these gives [significant results relating to] agriculture.

The world's northernmost dairy is Tine Tana, and it employs around 30 people.

The Tana Valley is the core area for "the River-Sami Culture" in Finnmark; salmon fishing is central in regard to that culture. According to written sources since the 17th century, fishing has been a major livelihood for the Sami people in the river valley of Tana River.

The Church of Norway has two parishes (sokn) within the municipality of Tana. It is part of the Indre Finnmark prosti (deanery) in the Diocese of Nord-Hålogaland.

Churches in Deatnu-Tana

Parish (sokn)	Church name	Location of the church	Year built
Tana	Austertana Chapel	Austertana	1958
	Tana Church	Rustefjelbma	1964
Polmak	Polmak Church	Polmak	1853

All municipalities in Norway are responsible for primary education (through 10th grade), outpatient health services, senior citizen services, welfare and other social services, zoning, economic development, and municipal roads and utilities. The municipality is governed by a municipal council of directly elected representatives. The mayor is indirectly elected by a vote of the municipal council. The municipality is under the jurisdiction of the Indre og Østre Finnmark District Court and the Hålogaland Court of Appeal.

The municipal council (Kommunestyre) is made up of 19 representatives that are elected to four year terms. The tables below show the current and historical composition of the council by political party.

The mayors (Norwegian: ordfører) of Tana (incomplete list):

Deatnu-Tana is situated along the lower river basin of the Tana River, which borders Finland along most of its course. People live in small settlements along the river, notably Sirma, Polmak, Rustefjelbma, Seida, Skiippagurra, Austertana, and Tana bru. Most inhabitants of Tana are Sami people, and the Sami language and culture are today promoted by the municipality and the schools. The highest point in the municipality is the 1,066.78-metre (3,499.9 ft) tall mountain Rásttigáisá.

The river Tana has represented a mainstay in the economy, as it is one of Europe's main salmon rivers, and it empties into the Tanafjorden. River transportation is traditionally done by long, narrow river boats, that are still in use, albeit motorized. Lakes in this area include Geassájávri, Nissojávri, and Sundvatnet. At Tana bru, the Tana Bridge (part of European route E6 and European route E75) crosses over the Tana River. The nearest airports are Vadsø Airport (about 70 kilometres or 43 miles away) and Kirkenes Airport (about 130 kilometres or 81 miles away). Kirkenes Airport (but not Vadsø) has direct flights to Oslo.

With the Tana River flowing through wild and spectacular habitat, the municipality of Tana has one of the most spectacular gatherings in Norway. As many as 25,000 goosanders can accumulate along the Tana waterway system. Add to this, thousands of common eider and long-tailed duck, then you have one of the largest concentrations of wildfowl in Norway.

In 2022 one bear was killed because of deaths of sheep from a local farm; An investigation deemed the killing of the bear, legal; The report said there likely had been at least one other bear in the municipality.

Tana has a subarctic climate (Dfc) with long, cold winters and short cool summers.

• Halvdan Wexelsen Freihow (1883 in Tana – 1965), a priest and culturist
• Per Fokstad (1890 in Tana – 1973), a teacher, politician, and intellectual of Sami origin
• Kathrine Johnsen (1917 in Tana – 2002), a Sámi teacher and worked for NRK Sápmi
• Kristen Kyrre Bremer (1925 in Tana – 2013), a theologian and bishop in the Church of Norway
• Per A. Utsi (d. 2024), politician, member of parliament
• Nils Utsi (1943 in Tana – 2019), a Sámi actor, stage director, and film director
• Ella Marie Hætta Isaksen (born 1998 in Tana), a Sami musician

• Reidar Hirsti (1925 in Tana – 2001), a newspaper editor, politician, and author of books about historical or Sami topics
• Nils Jernsletten (1934 in Tana – 2012), a professor of Sámi at University of Tromsø and editor of Sámi newspaper Ságat
• Marry A. Somby (born 1953 in Tana), a Sami author
• Hanne Ørstavik (born 1969 in Tana), a Norwegian writer
• Siri Broch Johansen (born 1967 in Tana), a Sami author, singer, and textbook author

• Martin Schanche (born 1945), nicknamed Mister Rallycross, a former racing driver and politician who was brought up in Tana
• Sigleif Johansen (born 1948 in Tana), a former biathlete
• Signe Trosten (born 1970 in Tana), a former biathlete
• Signe Marie Store (born 1995 in Tana), a freestyle wrestler

• Municipal fact sheet from Statistics Norway (in Norwegian)