Christianshavn (lit. '[King] Christian's Harbour') is a neighbourhood in Copenhagen, Denmark. Part of the Indre By District, it is located on several artificial islands between the islands of Zealand and Amager and separated from the rest of the city centre by the Inner Harbour. It was founded in the early 17th century by Christian IV as part of his extension of the fortifications of Copenhagen. Originally, it was laid out as an independent privileged merchant's town with inspiration from Dutch cities but it was soon incorporated into Copenhagen proper. Dominated by canals, it is the part of Copenhagen with the most nautical atmosphere.

For much of the 20th century a working-class neighbourhood, Christianshavn developed a bohemian reputation in the 1970s and it is now a fashionable, diverse and lively part of the city with its own distinctive personality. Businessmen, students, artists, hippies and traditional families with children live side by side.

Administratively, Christianshavn has been part of Indre By since 2007, but it still has its own local council.