Uruguaytherium is an extinct genus of astrapotherid mammal from the Late Oligocene to Early Miocene of South America.

It was named by the Argentinean paleontologist Lucas Kraglievich in 1928, from a fragmentary fossil found in the Fray Bentos Formation of the department of Río Negro in Uruguay, and the type species is U.

[1] The related genera Xenastrapotherium and Granastrapotherium, which make up Uruguaytheriinae with Uruguaytherium, are also from South America, although them colonizated the equatorial zone.

[2] The holotype specimen of Uruguaytherium is a partial mandible (the left mandibular ramus), with a preserved third molar, or M3.

[3] Cladogram based in the phylogenetic analysis published by Vallejo-Pareja et al., 2015, showing the position of Uruguaytherium:[2] Eoastrapostylops Trigonostylops Tetragonostylops Albertogaudrya Scaglia Astraponotus Maddenia Comahuetherium Parastrapotherium Astrapotherium Astrapothericulus Uruguaytherium Hilarcotherium Xenastrapotherium Granastrapotherium