Gahnia melanocarpa, known as the black fruit saw-sedge, is a tussock forming perennial plant in eastern Australia.

Often found in the wetter forests or in rainforest margins, it is common on the coast but also seen in the tablelands.

The flowers grow in spikes from the centre of the plant and appear in spring and summer.

[1] The specific epithet melanocarpa translates from the Greek meaning "black fruit".

[2] The species first appeared in scientific literature in Prodromus Florae Novae Hollandiae in 1810, authored by Robert Brown.