Ruyangosaurus is a genus of sauropod dinosaur recovered from the Late Cretaceous Mangchuan Formation of China. The type species is R. giganteus, described in 2009 by a group of scientists from the Chinese Academy of Sciences and the Henan Geological Museum. Along with Huanghetitan and Daxiatitan, Ruyangosaurus is among the largest dinosaurs discovered in Cretaceous Asia. Ruyangosaurus was described as being from the "early Late Cretaceous".