A new species of Serjania (Sapindaceae, Paullinieae), S. lucianoi from Northern Bahia, Brazil, belonging to Serjania sect. Eurycoccus, is described, illustrated, and compared to its putative closest relative. Serjania lucianoi seems to be related to S. glutinosa, and can be distinguished from it by: the 5-foliolate leaves, linear stipules, indument with simple and glandular obconical-headed trichomes, fruits with ovate outline, and seeds in basal portion of the locule. In addition, micromorphological characters of leaf and flower epidermis are given, and pollen grains are described. The new species is known only from Bahian caatinga, being an element of the dunes of the São Francisco River. We present a key to the Brazilian species of Serjania restricted to this biome.