Abstract: There were remarkable differences in sedimentary facies and palaeogeographic features and filling patterns in the northern and southern parts of the Jiyuan Basin during the Mesozoic. The southern part was uplifted,while the northernone subsided inheritedly during Early and Middle Jurassic time. The basin was completely closed at the end of Middle Jurassic. The differences outlined above are interpreted to be caused by the synsedimentary faulting of the Huanghe fault within the basin.