Cossinia is a genus of four species of rainforest trees, constituting part of the plant family Sapindaceae.

[2] The genus has a disjunct distribution, occurring in Mascarene Islands, Australia, New Caledonia and Fiji.

Cossinia trifoliata trees, endemic to New Caledonia, have become vulnerable to global extinction according to the International Union for Conservation of Nature (IUCN)'s 1998 assessment.

[7][8] Within their known endemic region the trees grow naturally in habitats which have historically had their native vegetation extensively destroyed and as of 2013[update] have been further threatened.

The publication includes descriptions of the species Cossinia pinnata and C. triphylla, named earlier by Philibert Commerson.