Two thousand one hundred and ninety teleosts belonging to 11 species and forty eight elasmobranchs of two species, collected from major landing centres along the south-west coast of India, were examined for metazoan parasites. Of the teleosts 83.65% and of the elasmobranchs 93.75% were found infected with different metazoan parasites. The parasites include 3 species of monogenetic trematodes, 10 of digenetic trematodes, 6 of adult oestodes, a number of larval cestodes belonging to the orders Pseudophyllidea, Tetraphyllidea and Trypanorhyncha and two of uncertain identity, one species of acanthocephalan, 6 genera of nematodes, 17 species of copepods and 4 of isopods. Of the parasites obtained Neogonapodasmius hemirhanmphi. gen., n. sp. (Digenea), Lernaeenicus epinepheli n. sp., and Paeonodes mugllis n. sp. (Copepoda) and Codonophilus hemirhamphi n. sp. (Isopoda) are new finds. Except the monogeneans, copepods and isopods, all others are reported for the first time from the southwest coast of India. The incidence and intensity of infestation and the nature and extent of damage by each group of parasites, as well as the importance of a detailed study of parasites and similar associates in massive fish culture programmes are discussed.