A key to forty-one species in ten parmelioid genera [Bulbothrix (4 spp.), Canoparmelia (1 sp.), Hypotrachyna (7 spp.), Myelochroa (1 sp.), Parmelina (2 spp.), Parmelinopsis (1 sp.), Parmotrema (18 spp.), Relicina (2 spp.), Rimelia (3 spp.) and Xanthoparmelia (2 spp.)] from New Caledonia is provided, in addition to brief taxonomic descriptions as well as notes on distribution. Five of the forty-one species are endemic to New Caledonia, and thirteen are new records for the island. Several old names used in the literature are clarified.