The Big-eared Opossum (Didelphis aurita), also known as a saruê, is an opossum species from South America. It is found in Argentina, Brazil and Paraguay.

This species, which was considered a population of the common opossum (D. marsupialis) for some time, was originally described as D. azarae by Coenraad Jacob Temminck in 1824, but this name was incorrectly given to the white-eared opossum (D. albiventris) for over 160 years. As such, the name azarae has been abandoned.

Due to carrying offspring, female big-eared opossums tend to stay in smaller areas and reduce their movements.