Context Analyze the multiple dimensions of biodiversity under a local and landscape lens in natural habitats, such as Amazonian savannas, is fundamental for the conservation of species and ecosystems. Objectives We aim to explore how landscape forest cover and patch-level variables affect the patterns of species abundance, functional traits, and taxonomic, functional and phylogenetic α-diversity of Phyllostomid bats in forest patches of the Savannas of Amapá, in both the wet and dry seasons. Methods We used mist nets to survey bats in 26 forest patches. We also quantified forest cover in buffers of 500, 1000, 1500, 2000 and 2500 m around each patch, and tree height, basal area, canopy cover, and vegetation clutter in the understorey at the patch level. We used hierarchical partitioning to relate the different indices with our predictor variables. Results Taxonomic, functional and phylogenetic diversity in the wet season increased with the proportion of forest cover in the 2500 m buffer. Vegetation clutter was negatively related to taxonomic and functional diversity in the wet season. In the dry season, average tree height positively affected taxonomic and functional diversity. Patch-level variables were more important than forest cover in explaining the average functional traits in both seasons. Conclusion We found seasonal variation in the relationships between components of bat diversity and different drivers. Since both forest cover in the landscape and patch-level variables are important for Phyllostomid bat diversity, conservation plans should consider forest conservation at the landscape level and maintenance of forest patch quality.