We present here a taxonomic synopsis of the native representatives of the family Acanthaceae in Paraíba State, northeastern Brazil. Fertile material was collected during monthly excursions between November 2014 and November 2015. We also analyzed specimens deposited in the Lauro Pires Xavier (JPB) and the Jayme Coelho de Moraes (EAN) herbaria, as well as consulted the REFLORA—Virtual Herbarium of the Flora and Fungi from Brazil and the Species Link databank. Taxonomic identifications were based on morphological analyses and consulting the literature. A total of 24 species belonging to 10 native genera were encountered, 11 species being reported for the first time for Paraíba State in this work. The most representative genera were Ruellia L. (8 spp.), Justicia L. (6 spp.), Harpochilus Nees (2 spp.), and Hygrophila R. Br. (2 spp.); the other genera were represented each by a single species. A key to the species, illustrations, and data concerning their geographic distributions, flowering, and fruiting are included. Additionally, a lectotype is designated for Beloperone thunbergioides and a neotype for Hygrophila costata and Justicia imbricata.