The present work was undertaken in the Cachoeira do Retiro “Quilombola” community, located in the municipality of Santa Leopoldina (20°06′04″S × 40°31′47″W), in Espírito Santo State, Brazil. We expected to encounter high levels of ethnobotanical knowledge in the community due to its distance from the principal local urban center and its localization in a region of high biodiversity. Field work was undertaken between August 2005 and August 2006, employing semi-structured interviews, participant observation, artifact-interviews, as well as the “walk-in-the-forest” technique in the company of a local specialist. Ten additional informants participated in the research (seven women and three men with ages between 42 and 84) who were identified using the “snow-ball” method. A total of 192 ethnospecies belonging to 188 distinct plant taxa were cited (with 59% being native to the Atlantic Forest biome) and were classified into the following use-categories: medicinal (52%), food (34%), construction (18%), technology (10%), ritualistic (5%), ornamental (5%), and fuelwoods (2%). The plants with the greatest Use-Values were Attalea humilis (1.3) and Polyandrococos caudescens (1.1). The Diversity Index of the community’s ethnobotanical knowledge (5.12 nats) was found to be higher than seen in other ethnobotanical studies undertaken in the Atlantic Forest. Using a methodology for determining conservation priorities it was found that 17 of the 49 species analyzed should be examined more closely in studies that could help guarantee the continuity of their populations in the local forest fragment in light of their low density and intense utilization by the Retiro Quilombola community.