Several studies have described the clear influence of the flood pulse on the differential distribution of species and the existence of distinct phytophysiognomies along the topographic gradient in the floodplain. However, few similar studies have been carried out in igapó, and the results obtained so far allow us to verify that there is some variation in species composition according to the duration of flooding; however, the existence of species zonation along the gradient has not been described so far. The aim of this study was to verify the influence of hydro-edaphic factors on the floristic composition, richness, diversity, basal area and density of individuals in the igapó forest of the Jaú National Park (Amazonas, Brazil), as well as to identify the existence of species zonation along the flooding and edaphic gradients.