<p>With the continuous expansion of urban areas, it becomes crucial to understand how the urban environment influences the functioning and the evolution of populations of urban exploiters, especially for species likely to cause damage. In this study, we examined whether the urban food availability, burrow access, proximity to water and large constructions positively affects the presence and the density of brown rats. To this end, we used two complementary databases of the city of Paris, containing information on rat presence and rat complaints. We then mapped these occurrences using a geographic information system (GIS) at the level of the 992 Parisian blocks, which are created for French statistical information (IRIS blocks). From the two databases, we first estimated the presence and density of rats of the 992 IRIS blocks and we correlated them with 14 urban environmental factors linked to food availability, burrow access, proximity to water and large constructions. Rat control intervention occurred in 378 IRIS blocks (38.1%) with an average density of 2.84e-5 ± 1.86e-6 interventions per square meter and rat sighting report occurred in 381 IRIS blocks (38.4%) with an average density of 1.50e-3 ± 1.17e-4 reports per square meter. Our results show that the presence and/or density of rats of our two databases were positively influenced by four of the seven proxies for food availability and by four of the five proxies for potential burrowing sites (especially the green spaces). Similarly, water proximity was also found to be an important factor explaining the density but not the presence of rats. However and contrary to our prediction, large constructions were not a crucial factor explaining the presence and density of brown rats. In conclusion, our studies confirm that food availability, green spaces (burrow access) and water proximity were the main crucial factors determining the presence and density of brown rats in cities.</p>