The lichen genus Ramalina is well represented on the Azores islands, an isolated archipelago in the Atlantic Ocean. Fieldwork on several islands, loans from several herbaria, and the collecting of fresh samples, allowed us to identify lichen substances by TLC and to estimate the phylogenetic placement of taxa using ITS sequences from many samples. This confirmed the presence of 13 species, including R. portuensis as new to the Azores and new to Greece. Evidently the Ramalina biota of the Azores is considerably different from that of the Canary Islands and Madeira, by the lower number of species and by their affinities. A commented survey of all reported species, both accepted and rejected, is provided, and an identification key is added. Keywords: biodiversity; identification key; integrative taxonomy; lichenized fungi; phytogeography.