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Nowadays, the infraorder Delphinida (oceanic dolphins and kin) represents the most diverse extant clade of Cetacea, with delphinids alone accounting for more than 40% of the total number of living cetacean species. As for other cetacean groups, the Early Miocene represents a key interval for the evolutionary history of Delphinida, as it was during this time span that the delphinidans became broadly distributed worldwide, first and foremost with the widespread genus <i>Kentriodon</i> and closely related forms. Here, we report on a new odontocete find from Burdigalian (20.4–19.0 Ma) deposits of the Friulian-Venetian Basin of northeastern Italy, consisting of the partial cranium of a small delphinidan with associated ear bones (right periotic, stapes, malleus and tympanic bulla). Osteoanatomical considerations and comparisons allow us to assign the studied specimen to the genus <i>Kentriodon</i>. This is the first confirmed record of <i>Kentriodon</i> from Europe as well as from the whole proto-Mediterranean region. Stratigraphic and phylogenetic considerations suggest that our new specimen may represent the geologically oldest member of <i>Kentriodon</i>. The evolutionary success of <i>Kentriodon</i> may correlate with the emergence of narrow-band high-frequency echolocation as a possible strategy to escape acoustic detection by large marine predators such as the squalodontids. In addition, the relatively high encephalization quotient of <i>Kentriodon</i> spp. may have provided these early dolphins with some kind of competitive advantage over the coeval non-delphinidan odontocetes.