Nova Baden State Park (NBSP) is located in the Brazilian Atlantic Forest which is a biodiversity hotspot and priority for conservation. Our aim is to provide a list of large and medium-sized mammal species recorded in NBSP. We made a camera trap survey and opportunistic observations from December 2014 to September 2015, and searched the grey literature. We recorded 12 large and medium-sized mammals in our survey and 11 more species listed in grey literature. The 23 species registered for NBSP belong to eight orders (Carnivora, Primates, Rodents, Cingulata, Pilosa, Didephimorphia, Lagomorpha and Artiodactyla), including threatened species at local, national and global levels. With an important mammal biodiversity, we concluded that avoidance of poaching and the control of domestic dogs need to be priorities for biodiversity conservation of NBSP, with a political management that includes the local community in Park activities.