The type specimen of "Dinocephalosaurus" was first discovered in 2002, during fieldwork conducted in Yangjuan Village, Xinmin District, Panxian County, Guizhou, China. It consists of a nearly-complete skull missing the left side of the jaw, as well as several associated cervical vertebrae. It was subsequently stored at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing, China under the collection number IVPP V13767, and a research paper describing the specimen was authored by IVPP paleontologist Chun Li and published by "Acta Geologica Sinica" in December 2003.