In the original description, it was included with Iguanodon and Ouranosaurus in a family Iguanodontidae (Horman, 1998).
Similar sails are seen in the unrelated dinosaurs Spinosaurus and Ouranosaurus, as well as the pelycosaurs Dimetrodon and Edaphosaurus.
Lurdusaurus was contemporaneous with the bizarre large theropod Suchomimus, which some believe to be synonymous with the slightly earlier Baryonyx from England, and with the sympatric Ouranosaurus, notable for its tall-spined vertebrae.