Sunndal is a municipality in the Nordmøre region located in the northeast part of Møre og Romsdal county, Norway. The administrative center of the municipality is the village of Sunndalsøra. Other villages include Gjøra, Grøa, Hoelsand, Jordalsgrenda, Romfo, Ålvund, Ålvundeidet, and Øksendalsøra. With an area of 1,713 square kilometres (661 sq mi), it is the largest municipality in Møre og Romsdal county. The important occupations in Sunndal include industry (with Hydro Aluminium Sunndal as the biggest employer), public services, retail, and farming.

The 1,713-square-kilometre (661 sq mi) municipality is the 47th largest by area out of the 356 municipalities in Norway and it is the largest in Møre og Romsdal county. Sunndal is the 141st most populous municipality in Norway with a population of 7,110. The municipality's population density is 4.3 inhabitants per square kilometre (11/sq mi) and its population has decreased by 1.3% over the previous 10-year period.

The parish of Sunndal was established as a municipality on 1 January 1838 (see formannskapsdistrikt law). In 1854, the northern part of the municipality (population: 1,291) was separated to form the new municipality of Øksendal. This left 2,188 residents in Sunndal.

During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee. On 1 January 1960, the neighboring municipalities of Ålvundeid (population: 513) and Øksendal (population: 497) were merged with Sunndal (population: 5,851) to form a new, larger Sunndal municipality. Both Ålvundeid and Øksendal were historically part of the municipality before 1854. Then, on 1 January 1965, the Ålvund-Ålvundfjorden area of the neighboring Stangvik Municipality (population: 508) was transferred to Sunndal.

The municipality (originally the parish) is named after the Sunndalen valley (Old Norse: Sunndalr). The first element is sunnr or suðr which mean "southern". The last element is dalr which means "valley" or "dale". Historically, the name was spelled Sunddalen (or Sunndalen). In 1870, the spelling was changed to Sundalen. On 3 November 1917, a royal resolution changed the spelling of the name of the municipality to Sunndal, adding an "n" and removing the definite form ending -en.

The coat of arms was granted on 12 April 1983. The official blazon is "Vert, a wormwood plant argent" (Norwegian: I grønt en sølv malurt). This means the arms have a green field (background) and the charge is a Norwegian wormwood (Artemisia norvegica) plant. The plant 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 design was chosen in a competition for the municipal arms. This design was chosen since this plant species is only found in a few places in the world. It has its main European distribution in Sunndal and neighboring Oppdal in the Dovrefjell-Sunndalsfjella National Park and in Trollheimen landscape protection area. Small populations are also found in Ryfylke, Scotland, and the Ural Mountains, with another subspecies in the mountains of Northern America. This plant can be found in abundance in many places in the mountains of Sunndal well above tree line. The arms were designed by Svein Thuen Rasmussen. The municipal flag has the same design as the coat of arms.

The Church of Norway has four parishes (sokn) within the municipality of Sunndal. It is part of the Indre Nordmøre prosti (deanery) in the Diocese of Møre.

Churches in Sunndal

Parish (sokn)	Church name	Location of the church	Year built
Hov	Hov Church	Sunndalsøra	1887
Romfo	Romfo Church	Romfo	1821
	Gjøra Chapel	Gjøra	1935
Øksendal	Øksendal Church	Øksendalsøra	1894
Ålvundeid	Ålvundeid Church	Ålvundeidet	1848

Sunndal is bordered on the west by Molde Municipality and Tingvoll Municipality, on the north by Surnadal Municipality, on the east by Oppdal Municipality (in Trøndelag county) and on the south by Lesja Municipality (in Innlandet county).

In the southern part of the municipality lies the Dovrefjell–Sunndalsfjella National Park, home to a plentiful amount of impressive muskox. In the northern part is the Trollheimen and Innerdalen landscape protection areas.

The municipality centers around the Sunndalsfjorden and the river Driva. There are also many towering mountains including: Trolla, Storskrymten, Vinnufjellet (with peaks Dronningkrona and Kongskrona), Innerdalstårnet, Salhøa, Såtbakkollen, Skarfjellet, and Vassnebba. The Vinnufossen and Svøufallet waterfalls both lie near the river Driva.

Sunndalsøra has a temperate oceanic climate (Cfb). Atlantic lows can produce a strong foehn effect in winter as the air is forced over the mountains surrounding Sunndalsøra. Sunndalsøra has the national record high for January and February. The record high 32.1 °C (89.8 °F) is from July 2014, and the record low −18.9 °C (−2.0 °F) is from February 2010.

Sunndal Municipality is 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 Møre og Romsdal District Court and the Frostating Court of Appeal.

The municipal council (Kommunestyre) of Sunndal is made up of 27 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 Sunndal: