Abstract: The Permian and Triassic are the most important gasproducing formations in Chishui area,Guizhou province.The exploration of reservoirs in this area has been confined for a long time because the understanding of structure formulation and evolvement are unclear.Based on the analyses of large amount of data,main research results are proposed.The structures of the Permian and Triassic in Chishui area developed under the background of development of Sichuan basin.The EWtrending structures formed earlier and the NStrending structure later.The earlier EWtrending structures formed because of the structural compaction pressure of the Qianzhong palaeohigh to north while the later NStrending structures formed by the south induced stress action of the westnorthern structural stress in the east boundary of Sichuan basin.The EWtrending structures (especially,great EWtrending faults) generated anticlockwise smooth shearing activity in the NS structural movement stage due to the WStrending structural stress action.

Key words: genetic model of structure, EWtrending structure, NStrending structure, PermianTriassic, Chishui area