Abstract: The size of the backbone FZOi of active faults and its active intensity are major factors which affecto stability of the damsite in daliushu damsite district of heishanxia gorge. By analyzing basic framework of fracture structure, expatiate the controlling and affecting of the activity of F201 fault on a series of secoridary faults and F7(8)which is another major fault. By discussing the size of the F201 of active faults and its active intensity, consider that the F201 fault is longer than 60Km. The frenche have revealed seven paleoearthquake events since late Pleistocene, at least four among the seven paleoearthquake events are greater than Ms≥7.0.