The objectives of this study were to describe the composition of the vascular flora of a native vegetation remnant of the Atlantic Domain, located in Juiz de Fora, SE Brazil, to use floristic similarity analyses to compare its variation with three recognized plant habitats: Inselberg (rock outcrop), Forest Edge and Forest Interior, and to compare the results found with similar research published for other areas of the Atlantic Forests. Plant specimens were randomly collected throughout the area in fortnightly fieldwork carried out between April 2001 and January 2004, enriching the colection of the Herbarium of the Federal University of Juiz de Fora (CESJ). The total of species found was 375, distributed in 257 genera and 89 families. Fabaceae was the most representative family with the highest number of species (38), followed by Asteraceae and Rubiaceae (24), Melastomataceae (20) and Solanaceae (17). The richest habitat was the Forest Interior, with 251 species; followed by the Edge, with 211; and the Inselberg, with only ten. The similarity indices showed that all three habitats have very distinct in floristic composition. The results highlight the great value of forest fragments in the maintenance of local biodiversity.