Abstract: This paper, by the method of field research, discusses the geometric distribution and active character of the Northern Margin Fault of the Huaian Basin. The paper segments the fault according to its activity and then discusses the kinematic character of the fault. Research has proved that the fault is an active fault which has actived since Quaternary. The east segment has the higiest activity and its averagevertical slip rate is 0.21-0.22mm/a since the middle of the late Pleistocene; the activity of the middlesegment is secondary to the east one and the west segment has a minor activity. The active time of thefault has a migrating tendency from the southwest to northeast. Finally, the paper discusses the locationof the epicenter of 1628 M6 1/4 earthquake.