Kanakomyrtus (Myrtaceae) is a newly described genus endemic to New Caledonia. Kanakomyrtus myrtopsidoides, the generic type, is transferred from Eugenia. Five new species are described: K. mcphersonii, K. revoluta, K. dawsoniana, K. prominens, and K. longtpetiolata. The genus occurs in forests at elevations between 500–1,600 m on the relatively mesic windward side of the Grande Terre. It is distinct from other baccate genera of Myrtaceae by a combination of linear stylar lobes, densely glandular stamens and stigmas, and a short but densely hoary indumentum that is brownish when dry. The thinly membranous partitions that partially extend between the seeds of some species suggest a close relationship to Archirhodomyrtus and some species traditionally placed in Rhodomyrtus. and Octamyrtus. Four of the six species have unisexual flowers, but much additional field work is needed to assess the reproductive biology of the genus. Following IUCN guidelines, four species are proposed as either Endangered or Critically Endangered, whereas the remaining species are considered Vulnerable and of Low Concern. Species descriptions, illustrations, distribution maps, and keys to species of the genus and related taxa of baccate Myrtaceae from New Caledonia are included.