Inselbergs are rocky outcrops that function as habitat islands. However, the extent of floristic isolation or connection among those habitats remains poorly understood, particularly in the Caatinga of Northeastern Brazil. In this study we examined the floristic composition of inselbergs in the Caatinga, Northeastern Brazil, and the associations among species across different habitats. Vascular plants were inventoried at the summit, karrens, joints, gnammas, and at the toeslope of the inselberg. We assessed floristic diversity, species similarity, growth forms, and the phytogeographic distribution of species within these habitats. A total of 134 species from 57 families were recorded. Ferns, lycophytes, and monocots accounted for 27 species, while eudicots comprised 107 species. The results indicate substantial alpha (alpha) diversity, with many species being habitat-specific. However, similarity analyses suggest that habitats with similar geoecological conditions tend to exhibit related floristic assemblages, implying a degree of connectivity among these vegetation islands. Our findings demonstrate that inselberg habitats in the Brazilian semi-arid region exhibit a dynamic and complex floristic composition, highlighting the importance of enhancing conservation efforts and expanding research on the ecological factors that shape biodiversity in these ecosystems.