Seaweeds inventory includes the species recorded on the coast of Uruguay and Argentina. These records combine data obtained from scientific papers, technical reports, databases and personal communications provided by specialists. Georeferences are consigned as latitudinal and longitudinal ranks when a continuous distribution is assumed, and with data-points in case of discontinuous distribution. The validity of seaweed taxa reported was checked with Algae Base (Guiry and Guiry, 2009) in order to update species names or higher taxonomic levels.