A well preserved Changshingian radiolarian fauna was obtained from bedded siliceous limestone and interbedded siliceous shale of the Dalong Formation in Shangsi area, Guangyuan, Sichuan, South China. The radiolarian species in each sample were identified, and the individuals in 1g samples ( sieved through 300 meshes ) were counted out. In general, most of the encountered specimens are Spumellaria and Entactinaria. Neither the abundance nor the diversity of it is high. The research shows that the abundance and diversity are closely related to sea level changes of Changhsingian age at the Shangsi Section. Where abundance and diversity reached higher values, the sea level would have peaked ( marine flooding surfaces ). The abundance and diversity of radiolarians from the early Changhsingian is greater than that of the late Changhsingian age, which coincides with the opinion that the marine water was deeper in the early Changhsingian than that in the late Changhsingian. Furthermore, foraminifer and radiolarian abundance showed a good negative correlation which may be caused by their different living habits and changes of water depth. Analysis shows that: the development of the Late Permian radiolarian fauna of the Shangsi Section, may result from changes of water depth.