Thryptomene longifolia is a species of flowering plant in the family Myrtaceae and is endemic to inland areas of South Australia.

The flowers are scattered along the branchlets singly or in groups of up to three on a peduncle about 1 mm (0.039 in) long.

The floral cup has five longitudinal ridges and the sepals are more or less round, pink, and about 1 mm (0.039 in) long.

[2] Thryptomene longifolia was first formally described in 1986 by John Green in the Flora of South Australia from specimens collected by T.R.

[4] This thryptomene grows on red sand dunes in the north of South Australia.