Banksia paludosa, commonly known as the marsh or swamp banksia, is a species of shrub in the plant genus Banksia. It is native to New South Wales, Australia, where it is found between Sydney and Batemans Bay, with an isolated population further south around Eden. There are two recognised subspecies, the nominate of which is a spreading shrub to 1.5 m (5 ft) in height, and subsp. astrolux is a taller shrub to 5 m (16 ft) high found only in Nattai National Park.