The evolution of the environmental legislation and the occupancy of river banks located in urban áreas supports the research based in the case study of the River Rainha, in the city of Rio de Janeiro, RJ, with the delimitation of the riparian zone with the use of the Geographic Information System (GIS) and field survey. Initially, maps were elaborated with the identification of the Rainha River, the legally protected riparian áreas applicable in accordance with the parameters set in the Brazilian Forest Code, and the legally protected riparian áreas applicable according to the parameters set out in Rio de Janeiro State Legislation. Finally, a map was elaborated with the representation of the juxtaposition of the legally protected riparian area and the buildings along the banks of Rainha River, showing the average of legally protected riparian area along the Rainha River occupied with buildings along with a analyses of this situation.