MSM P4166, a specimen from the Moreno Hill Formation (middle Turonian) of New Mexico, is described as the holotype of a new genus and species of hadrosauroid dinosaur. Jeyawati rugoculus, gen. et sp. nov., is diagnosed by a rugose texture that covers the entire lateral surface of the postorbital and the presence of a large neurovascular foramen at the base of the jugal process of the postorbital, as well as a unique combination of characters. A preliminary phylogenetic analysis reveals that Jeyawati is a basal hadrosauroid more derived than Probactrosaurus, Eolambia, and Protohadros, but more basal than Shuangmiaosaurus, Bactrosaurus, and Telmatosaurus. Assessment of ontogenetic criteria indicates that MSM P4166 represents a subadult or adult individual. Even with the recognition of Jeyawati, Late Cretaceous hadrosauroid biogeography remains somewhat ambiguous because of the lack of material from the late Turonian—early Santonian in western North America.