The Ruyang Basin is a Mesozoic—Cenozoic basin in western Henan Province. The clastic rock series overlapping the Jiudian Formation in the Ruyang Basin had been divided into the Paleogene Chenzhaigou Formation, Mangchuan Formation and Shitaijie Formation by geologists. Due to the discovery of Ruyang Giantic Sauropod DinosaurianFauna in the original Mangchuan Formation in 2006, it is necessary to restudy the clastic rock series. On the basis of large scale geological mapping, section measuring, collecting fossils of invertebrates, microbiota and vertebrates, and samples of radioactive isotopes dating, stable isotopes, geochemistry, as well as rock slices in this area, we conclude that the clastic rock series distributed in central part of the Ruyang Basin (Shangdian — Liudian Area), the original Chenzhaigou Formation and Mangchuan Ormation should be dated to the Cretaceous. This paper suggests that the Cretaceous Xiahedong Formation, HaoLing Formation and Donggou Formation represent the dinosaur bearing clastic rock series