We studied 86 species of hummingbird-pollinated flowers and their pollinators at a coastal lowland site and two highland rain forest sites in southeastern Brazil. The Jaccard index for hummingbird-pollinated floras showed greater floristic similarity between the two highland communities than between floras of high altitudes and that of near sea level. The lowland site had slightly greater richness than either of the two highland sites. Bromeliaceae was the most important family, accounting for ca 36 percent of the bird-pollinated species and comprising 33 percent of the richest flowers. The plant populations bloomed annually for the most part. Both the wet lowland and the dry highland floras showed flowering seasonality, whereas the cloud highland flora had aseasonal flowering. A hermit hummingbird was the major pollinator in the lowland community. A hermit and a non-hermit hummingbird shared most of the floral resources in the two highland communities. Hermit hummingbirds are the major pollinators of hummingbird-pollinated floras in the Atlantic rain forests of southeastern Brazil. These areas may be as rich as Central and other South American areas in hummingbird-pollinated flowers, and altogether present an older development history when compared to the North American flora.