Abstract: The Chuxiong Basin in central Yunnan is a Mesozoic peripheral foreland basin. The basin was (developed) mainly during the Late Triassic, and may be considered as one of highly prospective areas for oil and gas exploration in southern China. The integration of the data on palaeomorphology, sedimentary facies, palaeontology, grain sizes and trace elements has disclosed that the eastern part of the Chuxiong Basin was once in a (restricted) marginal sea environment during the Carnian and early Norian (i.e. Pujiacunian); a delta (environment) during the late Norian i.e. Ganhaizian) and Rhetian (i.e. Shezian), and a nonmarine environment closely (associated) with seas during the Jurassic, which may be supported by the evidences from several phases of (transgressions) during the Middle and Late Jurassic.