Orthaspidotherium was a European Paleocene genus of early herbivorous mammals of the family Phenacodontidae. It was included in the family Meniscotheriidae by Teilhard de Chardin in 1921-1922 and was subsequently separated into the subfamily Pleuraspidotheriinae, before being placed in the family Phenacodontidae where it remains today. The first complete skull, of Orthaspidotherium edwardsi, was described in 2010.