[2][3][4][5] Banksia benthamiana was first formally described in 1964 by Charles Gardner in the Journal of the Royal Society of Western Australia.

Using morphological cladistics, Kevin Thiele placed it in a group with B. audax and B. laevigata, based on very small distinctive seedling leaves, and linear pollen presenters.

It grows on plains in shrubland, sometimes as an emergent plant, on brownish yellow sandy loam or clay-loam, sometimes over laterite.

[4][9] Banksia benthamiana is currently classified as "Priority Four" by the Government of Western Australia Department of Parks and Wildlife,[3] meaning that is rare or near threatened.

[12] Banksia benthamiana is almost unknown in cultivation and unsuitable for small gardens, but can be grown in a container and is fast growing.