Persoonia filiformis is a species of flowering plant in the family Proteaceae and is endemic to the south-west of Western Australia.

It is a small, erect shrub with hairy young branchlets, linear leaves and greenish yellow flowers borne singly or in groups of up to twenty on a rachis up to 30 mm (1.2 in) long.

Persoonia filiformis is an erect shrub that typically grows to a height of 7–40 cm (2.8–15.7 in) with thin bark and branchlets that are hairy when young.

[2][3][4][5] Persoonia filiformis was first formally described in 1994 by Peter Weston in the journal Telopea from specimens he collected near the turnoff to Jurien Bay from the Brand Highway in 1980.

[3][4] Persoonia filiformis is classified as "Priority Three" by the Government of Western Australia Department of Parks and Wildlife[5] meaning that it is poorly known and known from only a few locations but is not under imminent threat.