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There is little meiofauna data from the southwest Atlantic, and especially lacking are studies examining deep-seacommunities. In this study, the structure of meiofauna communities, particularly nematodes, was analyzed from dataderived from 101 samples (48 samples on the continental-slope and 53 samples at a deep-sea site) collected at CamposBasin, SEBrazil. Differences in the meiofauna densities and in the number of taxa between continental slope and deepseasites depended on the taxonomic level examined. While total meiofauna abundance did not differ significantlybetween sites, nematode densities were significantly higher in the deep sea (mean of 157 inds.10 cm2) than on the slope(mean of 129 inds.10 cm2). The number of meiofauna taxa was significantly higher at the continental slope site. Yet forthe most abundant meiofaunal group, the nematodes, whilst the number of families did not differ between continentalslope and deep sites, the number of genera was significantly higher in the deep sea. The remarkable resemblancebetween the dominant nematodes (Halalaimus, Acantholaimus, Daptonema, Theristus and Sabatieria) from SEBraziland other deep sea studies confirmed earlier suggestions of a typical deep-sea nematode community with a broadgeographical distribution. Multivariate analysis derived from meiofauna and nematode data showed that the structureof the fauna differed significantly between sites. Correlations detected between meiofauna and some sedimentproperties, such as grain size and sediment heterogeneity, although significant, were very low.