Doodia is a genus of ferns in the Blechnaceae family, in the eupolypods II clade of the order Polypodiales, in the class Polypodiopsida. It is named after Samuel Doody (1656-1706), an English botanist. Distribution of the genus includes parts of Australia and New Zealand. Phylogenic studies have found Doodia to be embedded within the paraphyletic genus Blechnum. Christenhusz et al., 2011, therefore reassigned the Doodia species to Blechnum.