Abstract: At present, the large-scale grid-connection of distributed generation leads to the deterioration of power quality, and it directly threatens the secure and stable operation of power grid. To accurately evaluate power quality condition of power grid, a comprehensive power quality evaluation method based on subjective and objective variation coefficient combination weighting was proposed. Firstly, a method combining analytic hierarchy process (abbr. AHP) with criteria importance though intercrieria correlation (abbr. CRITIC) was adopted to carry out subjective and objective synthetic weighting. Secondly, the variation coefficient method was used to solve the comprehensive weight by which the abuses such as subjective randomness and objective one-sidedness could be effectively avoided. Finally, the results of analyzing practical data show that the proposed method simultaneously considers both subject and object factors, thus the results of comprehensive evaluation are more credible and reasonable．