The reproductive biology of shrubs and trees of a preserved savanna (cerrado) area in the municipality of Corumbatai, Sao Paulo State, Brazil, was studied. The floral sexuality of 135 species were characterized, with 85.2 % hermaphroditic, 9.4 % dioecious, 4.5 % monoecious, and one andromonoecious. Controlled pollinations were performed on 21 hermaphroditic species to determine the breeding systems. Nine apomictic species were found, all belonging to the Melastomataceae. Among the twelve sexual reproducing species, seven (58.3 %) proved to be self-compatible, and five (41.7 %) self-incompatible. Anemophily was found in five species, although pollination systems were not investigated in other species.