The aim of this work is to present new contributions to the knowledge of the genus Parmotrema in Argentina which arose from the study of herbarium specimens from the BAH collection of CTES herbarium, collected in northeastern Argentina. The material was studied following the conventional methodology for this group of lichens. About 200 specimens were studied among which 17 species were identified: five are cited for the first time for Argentina, the distribution of 12 previously recorded species is extended, and P. pseudocrinitum is excluded from the country. Descriptions and illustrations for the new records for Argentina and a key for the identification of the species of Parmotrema cited for the region are included. Keywords: Biodiversity; lichens; taxonomy.