The structures of assemblages of macroinvertebrate species in different rocky intertidal habitats within Keppel Bay, Queensland were investigated. Replicate sites of different habitats were sampled. The densities of 21 common sessile, predatory :or grazing animals were determined for 18 sites. Multidimensional scaling (MOS) and nonparametric multivariate analysis (ANOSIM) showed significant differences between species assemblages from habitats which differed in exposure to prevailing winds and in location on islands or the mainland. Species diversity of sessile animals was greater in exposed habitats while species richness of mobile molluscs was greater in sheltered habitats. The vertical distributions of the most abundant species within habitats are described. This study provides previously unavailable baseline data on rocky intertidal communities in this area. The possible ecological significance of associations of species with habitats are discussed.