This work was carried out with the main objective of sampling the herpetofauna of a Cerrado site in the state of Piauí, Brazil, that is influenced by neighboring biomes and one of the least known regions of the domain. The herpetofauna of the different habitats present at Estação Ecológica de Uruçuí-Una (EEUU) was sampled intensively during three campaigns (two during the wet season and one during the dry season). We recorded 90 species, 64 reptiles and 26 anurans, a high local richness when compared to other well-sampled localities of the Cerrado. The rarefaction curve for both anurans and lizards shows that the observed richness is close to real and the richness estimators indicate that undetected species should be added with higher sampling effort. Analysis of co-occurrence shows that the species are not randomly distributed in the landscape, indicating that they use preferentially particular types of habitat. Despite being located in a transitional area and influenced by neighboring biomes, the cluster analysis of similarity suggests that the herpetofauna of the EEUU is typical of the Cerrado. Thereby, the results of this study indicate that the EEUU presents a rich herpetofauna that plays an important role in the conservation of a regional faunistic pool.