In May 1950, upon request of the Minister João Alberto Lins de Barros, the Instituto Paulista de Oceanografia (São Paulo Oceanographic Institution) sent a delegation to She Trindade Island, situated on the south Atlantic at 20º 28' S. and 31º 46' W., to study the fishes. The expenses were defrayed by the Minister that had as it chief assignements an investigation of the abundance of the fishery resources of the region, to provide nourishing food for a population thac wIII be probably established on the island. Three scientific expeditions were engaged on the study of lhe Trindade fishes. The first was organized by the American Musem of New York (1912-1913), the second by the Museu Nacional, of Rio de Janeiro (1916) and the third by the Instituto Paulisía de Oceanografia (1950). During the course of the explorations, researches were carried out also at Cabo Frio, São João da Barra, and at the banks of São Tomé, Jaseur and Victoria; a collection of 153 fishes, now deposited in the Instivuto Paulista de Oceanografia, was obtained. This work is wholly based on a collection made by Prof. W. Besnard, Director of the Instituto Paulista de Oceanografia, and resulted in the recognition of 58 species of coastal and pelagic fishes from the entire region investigated. Among the main results of this scientific expedition, must be pointed out the occurrence of one species similar to Neopercis ledanoisi Cadenat, from Cabo Frio, that is now under investigation. At Trindade Island, was captured Kyphosus lutescens (Jordan & Gilbert), peculiar to the RevIIIa Gigedo Archipelago, Socorro and Clarion islands, of the Pacific region. It was also found, in the same collection, Balistes polylepis Steindachner from lower California and Peru, and Paracubiceps ledanoisi Belloc inhabiting the Westafrican coast.