Overall, 351 spiders from 25 families were collected on plots of twelve different vegetation areas at the NamibRand Nature Reserve (Namibia) between July and September 2007. The plots of eight vegetation areas, inhabited by the members of 23 families, were used to assess the influence of vegetation and vegetation structure on the appearance of the spider families on the plots, as well as spider density and spider diversity. The spiders could be divided into two different feeding guilds based on their hunting behaviour: active hunters and netdwellers. We found that the diversity and abundance of the active hunters was higher. Vegetation was classified into three biomes (Nama-Karoo, Desert, Transition-Karoo) and vegetation structure on each plot was analysed using plant species richness, vegetation cover and number of vegetation layers. The appearance on the plots varied between the families. Only the members of six families were found on five to eight plots; the members of the remaining families occurred only on three or fewer plots. Spider density was similar between Nama-Karoo and Transition-Karoo and noticeably less in Desert. Also the spider density varied between the plots of the Nama-Karoo but was similar between the plots of the Transition-Karoo. The α-diversity was highest on Transition-Karoo and considerably lower on Nama-Karoo and Desert. Concerning vegetation structure, family richness was highest at plots with high plant species richness and three vegetation layers. Nama-Karoo and Transition-Karoo displayed high similarity (β-diversity, SØRENSEN-Index), which was lower between the latter and the Desert biome. Keywords: Spiders, Namibia, diversity, vegetation, feeding guilds.