Steigen is a municipality in Nordland county, Norway. It is part of the Salten traditional region. The administrative centre of the municipality is the village of Leinesfjord.Steigen was established as a municipality on 1 January 1838 (see formannskapsdistrikt). The new municipality of Leiranger was separated from Steigen on 1 September 1900. On 1 January 1964, Leiranger was again merged with Steigen along with the neighboring municipality of Nordfold.
The municipality (originally the parish) is named after the old Steigen farm (Old Norse: Steig), since the first church was built there. The name is derived from the verb stíga which means "mount" or "rise" and it is referring to the high and steep mountain Steigtinden (tinden means "the peak") behind the farm.