The taxonomic treatment of Begoniaceae for the state of Bahia, Brazil, led to the recognition of three new species of Begonia with narrow distributions, which are described and illustrated here: B. delicata Gregório & J.A.S. Costa, sp. nov. is a herb restricted to the region of the Recôncavo; B. elianeae Gregório & J.A.S. Costa, sp. nov. is a shrub endemic to the Atlantic forest of the southern part of the state; and B. paganuccii Gregório & J.A.S. Costa, sp. nov. is a subshrub known only from the type material, collected in the Piedmont of Paraguaçu. Notes on morphology, comparisons with morphologically similar species, etymology, geographic distribution, habitat and phenological data for each species are also presented. Furthermore, keys are provided as an aid to separating the new species from congeneric species that occur in their surroundings. Due to the sparse knowledge of the new species, there is as yet insufficient data to accurately assess their conservation status.