Abstract: On the basis of remote sensing image interpretation, internal structural structure, new structure, seismic geological characteristics and chronological test, combined with the research results of small earthquake precise location and seismicity, this paper divides Hechi-Yizhou-Liucheng fault zone into four sections: north section (Nandan section), west section (Hechi section), middle section (Yizhou section), east section (Liucheng-Yingshan section), Among them, the western and middle segments were the most active, and they were still active in the middle and late Middle Pleistocene, the eastern segment was mainly active in the Middle Pleistocene, and the northern segment was mainly active in the early Pleistocene. The seismogenic structure is mainly in the northwest direction, supplemented by the northeast or near east-west direction, and the intersection of the northwest and the northeast or near east-west direction faults is the favorable place for the occurrence of medium strong earthquakes; the maximum magnitude of potential earthquakes in the east section and the north section is M_S 5.5, and the middle section is mainly active in the early Middle Pleistocene The maximum magnitudes of the potential earthquakes in the western segment and the western segment are M_S5.5 ~ M_S6.0.