Eostrix is a genus of extinct primitive owls in the family Protostrigidae, along with Oligostrix and Minerva. These owls date from the early Eocene of the United States, Europe, and Mongolia. They have been described based on fossil remains. The genus was created by Pierce Brodkorb in 1971 to place a fossil species known until that time as Protostrix mimica. The following species are recognised: In 2016, Gerald Mayr described E. gulottai from the early Eocene Nanjemoy Formation in Virginia. However, in 2022, Mayr, alongside Andrew C. Kitchener, moved 'E.' gulottai to the genus Ypresiglaux as the new combination Y. gulottai.