Despite the increase of knowledge about the southwestern Atlantic ichthyofauna, there is still a lack of information along extensive marine areas. The Espírito Santo state (ES) coast, considered a zoogeographic boundary and a transitional zone between tropical and subtropical realms, is still largely unknown. Here is provided a checklist containing 221 fish species at Franceses Island (south coast of ES), which was attained with data from 2000 to 2010 by means of underwater observations, specimen collections and fisheries monitoring. Abundance, habitats and threat risks of each species are shown and discussed. The number of reef fish species found at Franceses Island corresponds approximately to 35% of all fishes present in the Brazilian Province. The conservation of the Franceses Island and surrounding areas would protect a mosaic of environments that can support a high diversity of fish species.