Strictly Protected Areas and riparian forests in Brazil are rarely large enough or connected enough to maintain viable populations of carnivores and animal movement over time, but these characteristics are fundamental for species conservation as they prevent the extinction of isolated animal populations. Therefore, the need to maintain connectivity for these species in human-dominated Atlantic landscapes is critical. In this study, we evaluated the landscape connectivity for large carnivores (cougar and jaguar) among the Strictly Protected Areas in the Atlantic Forest, evaluated the efficiency of the Mosaics of Protected Areas linked to land uses in promoting landscape connectivity, identified the critical habitat connections, and predicted the landscape connectivity status under the implementation of legislation for protecting riparian forests. The method was based on expert opinion translated into land use and land cover maps. The results show that the Protected Areas are still connected by a narrow band of landscape that is permeable to both species and that the Mosaics of Protected Areas increase the amount of protected area but fail to increase the connectivity between the forested mountain ranges (Serra do Mar and Serra da Mantiqueira). Riparian forests greatly increase connectivity, more than tripling the cougars' priority areas. We note that the selection of Brazilian protected areas still fails to create connectivity among the legally protected forest remnants. We recommend the immediate protection of the priority areas identified that would increase the structural landscape connectivity for these large carnivores, especially paths in the SE/NW direction between the two mountain ranges.