Malarguesaurus is a genus of titanosauriform sauropod dinosaur from the Late Cretaceous of Mendoza Province, Argentina. Its fossils, consisting of tail vertebrae, chevrons, ribs, and limb bones, were found in the late Turonian-early Coniacian-age (~89 million years old) Portezuelo Formation of the Neuquén Group. The type species, described by González Riga et al. in 2008, is M. florenciae. Described as a robust sauropod, its closest known relatives may be Ligabuesaurus and Phuwiangosaurus. Like other sauropods, Malarguesaurus would have been a large quadrupedal herbivore.Malarguesaurus is the second sauropod dinosaur discovered in Mendoza Province; the first is Mendozasaurus neguyelap.