Caelorinchus mediterraneus is described from specimens collected in the western and central Mediterranean Sea (Catalan Sea, Ligurian Sea, Adriatic Sea) at depths between 800 and 1200 m. Previous workers had misidentified the species as C. occa, C. labiatus, or C. vaillanti (a synonym of C. labiatus). It differs from those species, in snout shape, squamation, color, and size (maximum length about 30 cm, compared to more than 40 cm), among other characters. The new species is one of the most abundant demersal fish in depths greater than 1000 m in the southern Adriatic and Catalan Seas. The widespread Atlantic species C. caelorhincus is the only other verified member of the genus found in the Mediterranean.