In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only genus in the family Oleandraceae, which is placed in suborder Polypodiineae, order Polypodiales.

The lamina (leafy area of the fronds) are simple or pinnate, and the individual pinnae are articulate to the rachis.

The sporangia are contained in discrete round sori in a single row on either side of the midrib of the fronds.

[citation needed] The following cladogram for the suborder Polypodiineae (eupolypods I), based on the consensus cladogram in the Pteridophyte Phylogeny Group classification of 2016 (PPG I),[1] shows a likely phylogenetic relationship between Oleandraceae and the other families of the clade.

Didymochlaenaceae Hypodematiaceae Dryopteridaceae Nephrolepidaceae Lomariopsidaceae Tectariaceae Oleandraceae Davalliaceae Polypodiaceae O. distenta O. articulata O. decurrens O. pilosa O. neriiformis O. pistillaris O. sibbaldii O. wallichii O. cumingii O. musifolia