"Dachongosaurus" is the informal name given to an undescribed genus of sauropod dinosaur from the Early Jurassic of China. It is known from fossils including at least a partial articulated skeleton from the Dark Red Beds of the Lower Lufeng Series (Sinemurian stage) in Yunnan. Possibly a cetiosaur, the "type species" is "Dachongosaurus yunnanensis", coined by Zhao in 1985. An alternate spelling is "Dachungosaurus". As with other informal names coined by Zhao in 1985 and 1983, nothing has since been published, and the remains may have been redescribed under another name.