According to the cases, the influence law of coupling beam's damage to the double earthquake fortification lines of frame-core wall system and its seismic performance is discussed.The results show that the coupling beam's damage is a major factor in reducing seismic forces, and the external columns are difficult to give full play to the seismic capacity before and after the core wall's severe damage.In the double earthquake fortification lines' design work, more attention should be paid on the core wall's double earthquake fortification lines, thus, it can make up the deficiency of outer frame.