Each year, temperate deciduous forests produce a layer of litter comprised primarily of leaves. Two common and diverse taxa found in the litter layer are ground beetles (Coleoptera: Carabidae) and ground spiders (Araneae: Gnaphosidae). We collected and identified these groups on a monthly basis from April 2014 to March 2015 at 4 sites in Northwest Arkansas to determine their abundance and diversity across the following 3 variables: season, litter depth, and site location. A total of 480 litter samples and 208 pitfall-trap samples were collected and processed. These samples resulted in 645 carabids representing 47 species and 421 gnaphosids representing 15 species. Statistical analyses detected significant differences in species richness, average number of individuals, and species diversity of gnaphosids among sites. In contrast, leaf-litter depth had no significant effect on the number of individuals collected, species richness (except at one site), or species diversity of carabids and gnaphosids. Both carabids and gnaphosids were most abundant and diverse during the spring.