Among environmental contaminants in the water, the heavy metals are relevant for being cumulative and can reach all the trophic chain. Depending on the environmental conditions, these elements may have mobility between sediment, water and plant biomass in an aquatic environment. The concentrations of heavy metals copper (Cu), cadmium (Cd), lead (Pb) and chromium (Cr) in sediment, in water and in two species of aquatic macrophytes (Eichhornia crassipes and Paspalun repens) identified in the Lagoa da Francesa (Parintins / AM) were measured and evaluated. The samples were collected in July 2012. Cd was not found in the macrophytes and in the sediment. Pb showed higher concentrations in the water. The metals Cu, Pb and Cr presented higher concentrations in the roots of macrophytes, whereas Paspalun repens macrophyte cumulated higher concentration of Pb in its shoots (leaves).