Oedaleops was first described by paleontologist Wann Langston, Jr. in 1965 on the basis of a mostly complete skull (specimen UCMP 35758, the holotype of Oedaleops) and a few isolated skull and postcranial fragments. The UCMP 35758 skull has been the sole specimen of Oedaleops used in most analyses of its evolutionary relationships. The more fragmentary specimens have been assigned to Oedaleops with caution because they are hard to distinguish from the bones of other Cutler Formation synapsids such as Aerosaurus. Additional specimens of Oedaleops were described in 2013, including many isolated dentaries (lower jaw bones), pectoral and limb bones, and disarticulated vertebrae representing at least three new individuals.