The osteology of the Eocene lizard Eolacerta robusta from Messel and Geiseltal is redescribed. Contrary to former opinions, Eolacerta does not possess body osteoderms, the pubis is typically lizard-like, the astragalus and calcaneum are fused, and the first cervical rib is distinctly curved posterolaterally. The suggestion that Eolacerta belongs to the modern family Lacertidae cannot be corroborated due to its many plesiomorphies and character incongruences, a view which is also supported by phylogenetic analysis. At present, Eolacerta cannot be assigned to any modern lizard family and is classified as Scleroglossa incertae sedis.