This is the first study on the epi- and hyperbenthic fauna of the surf zone of sandy beaches of the Belgian coast. Therefore, as a first objective of this thesis, a lot of attention has been paid to the inventarisation (species composition), and to the investigation of the temporal and spatial distribution patterns of both communities. A temporal and a spatial campaign were performed during which the hyper- and epibenthos was sampled. During the temporal campaign monthly samples were taken at 4 selected stations and the spatial campaign involved sampling of 12 stations along the Belgian coast. All in all, the surf zone of the Belgian coast is a habitat for a considerable number of species. The surf zone harbours a rich hyperbenthic fauna and also the epibenthic assemblage is diverse. Total hyper- and epibenthic densities were comparable or even higher than those of the adjacent, subtidal regions. It seems that the Belgian surf zone can be seen as an extension of the rich shallow sand bank system in front of the coast. Differences in total hyperbenthic densities with other European sandy beaches might be linked to the degree of exposure.An attempt was made to elucidate the major environmental variables structuring the communities. Therefore several environmental variables were measured at the moments of sampling. Different uni- and multivariate statistical techniques were used for the analyses of the data. Although clear temperature-related seasonal distribution patterns were observed, the hyper- and epibenthic communities of the surf zone can also be influenced severely by hydrodynamic factors and this both by short-term events (e.g. storm) and long-term effects (influence on morphodynamics of the beach). Spatial differences were found both in species richness and in density. In general, highest hyper- and epibenthic densities were found on flat, wide beaches, but also intermediate sites and sites with a high turbidity were characterised with high densities and a high number of species. Although clear ...