Patterns of diversity of bats in the Biosphere Reserve Selva El Ocote, Chiapas, Mexico. Bats have been considered as a model group for studies on biodiversity in the Neotropics. Taxonomic diversity and functional categories of bats were analyzed in the Selva El Ocote Reserve. Bats were captured using mist-nets, and environmental and vegetation data were collected in four localities between January and September, 2015. Alfa diversity was estimated using Hill's numbers and rarefaction-extrapolation and abundance-rank curves. Beta diversity was evaluated by similarity indexes and Wilson-Schmida's species- turnover index. Canonical Correspondence Analysis was performed to explore associations between bat species and functional categories and environmental and vegetation variables. We recorded 37 bat species, 17 to 27 species in the sampled localities; moreover, 14 restricted species among three localities. Phyllostomidae family and the frugivorous guild were the richest and most abundant groups, Artibeus jamaicensis was the most frequent species. We found association between bat diversity and the vegetation variables group (F= 1.6588, P= 0.005), however there were no associations with environmental variables. Positive relationship was found between floristic diversity and bat diversity (r = 0.94, P=0.001). The species Trachops cirrhosus and Dermanura tolteca were related positively with tree density and Artibeus lituratus, Dermanura phaeotis and Platyrrhinus helleri were associated with tree diversity. The bat assemblages presented high similarity, forming nested subsets. Forests fragments with less human intervention harbored mores species richness and habitat specialist bats, whose permanence will depend directly of the degree of forest conservation.