The subjective blindness and instability of the indicator weighting methods in the assessment of power system emergency management capability make the evaluation results difficult to truly reflect the power system emergency management capability. Therefore, the variable weight method based on the analytic hierarchy process and entropy weight method is adopted to calculate the indicator weight, and the grey comprehensive evaluation method is introduced to comprehensively rank the evaluation objects and point out their weaknesses. Finally, four power grid enterprises were taken as cases to assess the emergency management capability, and the weak links of power supply bureau C in emergency management were pointed out as follows: information processing and linkage, recovery and reconstruction. On the basis of subjectivity, objectivity and stability, the proposed weighting method uses variable weight to reflect the huge impact of extremely poor indicator values on the evaluation results, so as to make the evaluation method more comprehensive and scientific. In the follow-up study, time factor can be further included in the evaluation system.