Nuuk (Greenlandic pronunciation: ​[nuːk]; Danish: Nuuk, formerly Godthåb [ˈkʌtˌhɔˀp]) is the capital of and most populous city in Greenland, an autonomous territory in the Kingdom of Denmark. Nuuk is the seat of government and the territory's largest cultural and economic center. The major cities from other countries closest to the capital are Iqaluit and St. John's in Canada and Reykjavík in Iceland. Nuuk contains a third of Greenland's population and its tallest building. Nuuk is also the seat of government for the Sermersooq municipality. In January 2023, it had a population of 19,604.

The city was founded in 1728 by the Dano-Norwegian missionary Hans Egede when he relocated from the earlier Hope Colony (Haabets Koloni) where he arrived in 1721. The governor Claus Paarss was part of the relocation. The new colony was placed at the Inuit settlement of Nûk and was named Godthaab ("Good Hope"). "Nuuk" is the Greenlandic word for "cape" (Danish: næs) and is commonly found in Greenlandic place names. It is so named because of its position at the end of the Nuup Kangerlua fjord on the eastern shore of the Labrador Sea. Its latitude, at 64°11' N, makes it the world's northernmost capital, only a few kilometres farther north than the Icelandic capital Reykjavík. When home rule was established in 1979, the authorization of place names was transferred to Greenlandic authorities, who subsequently preferred Greenlandic names over Danish ones. The name Godthåb mostly went out of use over the next two decades.

The campus of the University of Greenland, hosting Statistics Greenland and the main holdings of the Public and National Library of Greenland, are at the northern end of the district, near the road to Nuuk Airport.

Nuuk receives its electric power mainly from the renewable energy-powered Buksefjord hydroelectric power plant by way of a 132 kV powerline crossing Ameralik fjord over a distance of 5,376 m (17,638 ft), the world's longest free span.