Rødøy is a municipality in Nordland county, Norway. It is part of the Helgeland traditional region. The administrative centre of the municipality is the village of Vågaholmen. Other villages include Gjerøy, Jektvika, Kilboghamn, Melfjorden, Oldervika, Sørfjorden, and Tjong. The municipality consists of many islands to the west of Norway's second biggest glacier, Svartisen.
The municipality of Rødøy was established on 1 January 1838 (see formannskapsdistrikt). On 1 January 1884, the northern district of Rødøy was separated to form the new municipality of Meløy. This division left Rødøy with 1,945 residents. The borders of the municipality have not changed since that Time.The Old Norse form of the name was Rauðøy. The first element is rauðr which means "red" (probably referring to the color of the rocks of the island) and the last element is øy which means "island".