Abstract: Sichuan Province is an important producing area of dinosaur fossil sites in China, and a series of dinosaur fossils were discovered in this area for a long time. In 2021, another group of fossils dominated by Sauropods, together with the Coelurosaur, Carnivora, Stegosaurus and turtles, was found in the upper part of Shaximiao Formation of Middle Jurassic in Wangcang County of Guangyuan City. It is a rare dinosaur fossil burial site with rich population, high density and concentrated distribution in China. Through geological mapping, profile disclosure, fossil statistics, microfacies analysis and other means, the authors comprehensively analyzed the lithologic association, structural characteristics and other factors, and concluded that the clastics source is from Longmen Moutain, Daba Mountain and Micang Moutain, and the sedimentary environment belongs to channel and interchannel microfacies of delta plain subfacies. The taphonomy characteristics indicate that these fossils were heterochthonousburial, and had not been transported for long distance. The further discovery of dinosaur fossils in Wangcang County strongly suggest that it has an advantageous condition for investigation, research and excavation of dinosaur fossils, which could provide some references for the in-depth research of pale-environment, paleoecologic change, and systematic evolution of basinal dinosaur in Sichuan Basin.