Jaxartosaurus (meaning "Jaxartes River lizard") is a genus of lambeosaurine hadrosaurid dinosaur similar to Corythosaurus or Hypacrosaurus which lived in Kazakhstan and China during the Late Cretaceous. It had a large, helmet-like crest that it may have used to identify an other member of the herd, attract a mate, or to 'talk' with members of the same herd. The type species, J. aralensis, was first described by Anatoly Nickolaenvich Riabinin in 1937.