The purpose of the present investigation is to evaluate the importance of the contribution of polychaetqus annelids to the feeding habits of fishes, crustaceans and molluscs from an important fishing area to the northern coast of São Paulo. Many of the species of fishes caught by otter-trawl, along the first phase of the present work have shown a remarkable preference for the polychaetes, as food items. Among them Rhinobatos horkelli, Orthopristis ruber. Cynoscion striatus, Menticirrhus americanus, Micropogon furnieri, Paralonchurus brasiliensis, Umbrina canosai, Etropus intermedius and Symphurus trewavasae are the most representative in this respect. The taxonomic analysis of the worms revealed the presence of 32 species, from which the more frequent was Nothria stigmatis, Pherusa laevis, Pherusa parmata, Piromis arenosus, Pectinaria laelia and Thelepus setosus.