Macaranga is a genus in the family Euphorbiaceae. It comprises trees, treelets and some lianas, many of which are conspicuous large-leafed pioneers of disturbed habitats. Some species have ant associations. There are 257 species, of which 21 are newly described here. The genus is most diverse in South East Asia and New Guinea but also occurs in Africa and Madagascar (37 species), continental Asia (30 species), the Pacific Islands (24 species) and Australia (7 species). The species can be identified with the help of either regional keys or keys within informal species groups. Twenty-five species are illustrated.