A taxonomic review of the New Caledonian representatives of the pantropical tree genus Xylopia L. (Annonaceae) is presented based on museum study of 157 collections. Distinctions are clarified among the four endemic species, two of them previously undescribed in flower and two others described in the literature from only the type collections. A key and species descriptions are presented. Xylopia pancheri Baill., the most frequently collected species, occurs in maquis environments with ultramafic rocks in the central and southern regions of the island, as well as on the Île des Pins. Xylopia vieillardii Baill. is widespread in low elevation humid forests but the remaining two species, X. dibaccata Daniker and X. pallescens Baill., have restricted distributions and their ecology is still incompletely known. Xylopia pancheri shares similarities with the endemic Fijian species X. degeneri A.C.Sm. and X. vitiensis A.C.Sm.; the remaining three species share more traits with the Fijian endemic X. pacifica A.C.Sm.