The faults were divided into single-stage active fault,growth fault and multi-stage active fault according to the fault activity period in the Gao89 area of Dongying sag. The fault activity of the three types ended in the order mentioned above,so their vertical safety becomes poorer correspondingly. According to the allocation relationship between the regional seal and the vertical extension of fault,the faults were divided into embedded type,lower broken type and broken through type,and the seal completeness of them decrease in the order,so the vertical safety becomes poorer correspondingly. According to the allocation relationship between the fault throw and the thickness of the direct seal,the faults were divided into intact top seal type,seal connected type and seal apart type,and the completeness of their direct seals decrease in the order,so their vertical safety become poorer correspondingly. The comprehensive evaluation system was established to evaluate carbon dioxide flooding and the vertical safety of the fault during carbon dioxide sequestration through analyzing fault activity periods,the allocation relationship between the regional seal and the vertical extension of fault,the allocation relationship between the fault throw and the thickness of the direct seal,the bonding section thickness of the direct seal and the fault dip in the Gao89 area. The results show that the allocation relationships between the regional seals and the vertical extension of faults are mostly embedded type and lower broken type. The allocation relationships between the fault throw and the thickness of the direct seal are the intact top seal type and the seal connected type without the seal apart type. The fault dip is between 40° and 65°. According to the study result,the vertical safety of faults are high in the Gao89 area.