The stromboid fauna from Cenozoic deposits of Chile contains an unusual mixture of warm-water and cool-water taxa, showing relationships with either Argentinian or New Zealand taxa. Six species of Strombidae, Aporrhaidae, and Struthiolariidae are described, and their relationships and paleobiogeographic implications are discussed. Conus medinaePhilippi, 1887 from the Miocene Navidad Formation is assigned to the genus Strombus and thereby constitutes the first record of Strombidae from southwestern South America. The new subgenus Austrombus is proposed for smooth species of Strombus without any spines or axial sculpture. Hemichenopus araucanus (Philippi, 1887) from the ?Eocene of Peninsula Arauco shows strong affinities to Dicroloma zelandicaMarshall, 1919 from the Eocene of New Zealand, which is here assigned to Hemichenopus. The New Zealand species Perissoptera (Hemichenopus) thomsoniAllan, 1926 does not belong in Hemichenopus but could not be reassigned to another aporrhaid genus. Struthiochenopus bandeli n. sp. and Struthiochenopus philippiiZinsmeister and Griffin, 1995 are reported from deepwater facies in Chile, rather than the nearshore facies favored by congeners in Argentina. Perissodonta ameghinoi (Ihering, 1897) and Perissodonta chilensis (Philippi, 1887) are the only species of this genus in the eastern Pacific, the former being an Atlantic species, reported for the first time from the Pacific. The term Neo-Weddellian is proposed for Miocene taxa having their origin in the Late Cretaceous–Paleogene Weddellian Province.