Five new species of longhorned beetles (Coleoptera: Cerambycidae) from the Dominican Republic are diagnosed, described, and illustrated: Ataxia hovorei, Atimiola rickstanleyi, Drycothaea indistincta, Eburia pseudostigma, and Hormathus giesberti. In addition, Hormathus Gahan 1890 is transferred from Tillomorphini Lacordaire into Ibidionini Thomson, Division V; Trinoplon Zayas 1975 is a new synonym of Hormathus; and Hormathus bicolor (Zayas 1975) is a new combination. A key to the three species of Hormathus is provided.