Leguminosae is dominant in vegetation formations of Amazon and, in this context the Marajó Archipelago stands out for including several of these formations. This paper aimed to update and analyze the patterns of geographic distribution of Leguminosae from the Marajó archipelago. Data obtained from herbaria, literature and botanical expeditions thus the patterns of distribution were determined. We registered 241 species in 80 genera of which six are new records for the flora of Pará State. The most representative genera were Inga, Mimosa, Aeschynomene and Machaerium. Subfamily Papilionoideae had the greatest number of genera and species. Jacqueshuberia quinquangulata is endemic to Marajó Island. The phytogeographical analysis showed predominance of species widely distributed South America. The archipelago, because of its physiognomic heterogeneity, represents a diverse site of Leguminosae in Amazon, with about 31% of species diversity mentioned for the family in Pará.
Amazon; Fabaceae; floristic survey; phytogeography