The objectives of the present contribution were (a) to describe the floristic composition and structure of the tree community of the forests of the Parque Ecológico Quedas do Rio Bonito, Lavras, Minas Gerais State, SE Brazil (21°20’S, 44°58’WGW, 1,000-1,300m of altitude); and (b) to assess the correlations between species distribution and environmental variables in three forest sections. Individual trees with the circumference at breast height (cbh), the total height and species name were registered for individuals with cbh ≥ 15.7cm surveyed in 80 plots of 10×30m of dimensions distributed into three transects spaced at 480m intervals. Environmental variables were obtained for each plot from textural and chemical analyses of soil samples (0-20cm of depth), and a topographic survey of the sample transects. The floristic survey carried out both inside and outside plots registered 384 species belonging to 182 genera and 68 families. The floristic features were characteristic of the montane forests of southeastern Brazil. The 4,137 trees and 213 species surveyed in the plots yielded a high Shannon diversity index (H’ = 4.56 nats.ind.-1) which was probably related to a high environmental heterogeneity and low ecological dominance. A canonical correspondence analysis (CCA) identified the edge factor and drainage class as the variables most strongly correlated with the species’ abundance distribution.