Banksia tenuis is a shrub endemic to Western Australia. It was known as Dryandra tenuifolia until 2007, when all Dryandra species were transferred to Banksia by Austin Mast and Kevin Thiele. As the name Banksia tenuifolia had already been published in reference to the plant now known as Hakea sericea (Needlebush), Mast and Thiele had to choose a new specific epithet; their choice, "tenuis", retains the original names' use of the Latin tenuis ("thin"), in reference to the narrow leaves.