Cassinia trinerva is a species of flowering plant in the family Asteraceae and is endemic to south-eastern Australia.

It is an erect shrub or small tree with hairy stems, narrow lance-shaped leaves, and flower heads arranged in dense corymbs.

Cassinia trinerva is an erect shrub or tree that typically grows to a height of up to about 8 m (26 ft), its branchlets sticky and covered with glandular and cottony hairs.

[2][3][4] Cassinia trinerva was first formally described in 1951 by Norman Arthur Wakefield in The Victorian Naturalist.

[5][6] This cassinia is an understorey shrub in tall forests, on the edge of rainforest and on dry rocky sites.