This study investigated the influence of soil factors on the structure, richness and distribution of woody Cerrado species within the National Forest of Paraopeba, Minas Gerais State, Brazil. Individuals with basal stem circumference $ 10 cm were sampled in five plots of 20 3 100 m. The study was conducted in five environments with different physiognomies and types of soils. A total of 132 species were recorded. The species with the greatest importance values varied between different areas, as did structure. Canonical correspondence analysis ordination showed three different groups closely related to soil fertility and Al levels. These relations were also confirmed by Pearson's correlation where richness was positively related to pH, K, Ca, Mg and P and negatively to Al. The basal area was positively correlated with levels of P, Mg, Ca and T (base saturation) and negatively with Al, also using Pearson's correlation. Likewise, density was positively correlated with Mg and negatively with Al. The analysis shows that soil fertility and the concentration of Al are two of the most important factors responsible for structural and floristic variation and for differentiating dystrophic and mesotrophic Cerradão.