A scuba diving census, in whichabundance and size class of structure of conspicuous fish species were determined, was used to assess the effects of depth ans marine reserve fishing restrictions on the structure oe a Mediterranean rocsky reef fish assemblage by comparing communities at sites from two depth ranges inside and outside a marine reserve.The total assemblage had thirty-fice conspicuous species and was dominated by labriadae (13 spp.) and sparidae (9 spp.).Mean species richchness (number of species) and diversity (Shannon) did not differ between sites.Ordination of abundance data showed that occurence and relative abundance of species was affected by depth (deep samples separated completely from shallow samples) and marine reserve status (samples from the marine reserve were significantly separated from those taken at the same depth outside the reserve).Samples from the same depth were similar, because the majority of species showed a preference fro either deep ar shallow areas. The known biology of several species indicated that feeding requirements may be responsible for depth preferences.Samples from reserve sites had signficantly higher sensities of hish species sought after and/or vulnerable to local fishing methods, than those from non-reserve sites of similar depth.Size frequency distributions of vulnerable species at reserve sites generally had a larger modal size class than distribution from non-reserve sites.The data suggest that reduced fishing pressure in the reserve has provided effective protection for species vulnerable to fishing.