The Parque Estadual da Serra do Papagaio (PESP) harbors some unusual fragments of mixed needle-broadleaved forest (MNF) of Minas Gerais state. This study aims to analyze the floristic composition and geographic distribution of the genera represented in the MNF of the PESP. Collections of fertile specimens of vascular plants (excluding epiphytes) were conducted monthly (March 2012–June 2013) in the alluvial and slope areas of MNF in the PESP, in altitudes ranging from 1,650–2,000 m above sea level. The genera were classified into seven phytogeographic groups that were delimited according to their current diversity centers available in the literature. We recorded 310 species belonging to 168 genera and 82 families of vascular plants. The richest families were Asteraceae (49 species), Melastomataceae (33 species) and Rubiaceae (16 species). We observed the presence of species often found in montane and high montane forests of southeastern region, besides of temperate genera, showing that low temperatures caused by high altitude influence the floristic composition of the area. The high richness found denotes the importance of altitude areas for diversity in Atlantic Forest and highlights the biogeographic importance of the region for presenting an unusual phytophysiognomy in the state with endemic and endangered species.