Habitat complexity influences the diversity and structure of biological communities by determining the availability and heterogeneity of environmental resources. Spiders, widely recognized as effective environmental bioindicators, are particularly sensitive to changes in habitat structure. This study evaluated how habitat complexity, measured through multiple environmental variables, affects the ground-dwelling spider community in gallery forests, and identified threshold points in species frequency and abundance in relation to these variables. Spiders were sampled using pitfall traps, and environmental variables including canopy cover, understory complexity, grass cover, soil pH and moisture, and litter cover, depth, weight, and composition were measured. A total of 36 samples were collected, yielding 1474 specimens distributed among 112 species/morphospecies and 31 families. The results showed significant interaction effects between canopy cover, litter depth, and litter composition on spider abundance. Furthermore, critical changes in variables such as canopy cover, grass cover, and litter cover, depth, and composition indicate that habitat structure plays a relevant role in the frequency and abundance of individual species. Leprolochus mucuge , Nosferattus sp.1, and Camillina sp.1 were identified as potential indicator species for monitoring environmental degradation in forested areas, while Epicratinus pikachu may serve as an indicator of forest conservation. These findings emphasize the importance of habitat structural for shaping species-specific responses and support the use of ground-dwelling spiders as bioindicators. The identification of indicator species provides valuable information for monitoring programs, management actions, and conservation planning in the Cerrado domain. • Habitat complexity shapes diversity in ground-dwelling spider communities. • Litter and canopy cover significantly affect spider abundance. • Thresholds identified for species response to habitat structure changes. • Key spider species indicate forest degradation or conservation status.