The invention discloses overall evaluation index system and method for smart grid construction. The method comprises the following steps: building a construction time-construction link overall evaluation framework according to the smart grid planning constructing characteristics; creating a set of target-action-effect three-stage type overall evaluation index system for the smart grid on that basis; determining the index item corresponding to each dimension of the all-process action evaluation system according to the target system arrangement; setting up evaluation criteria for indexes at all levels. The smart grid all-process action evaluation system comprises a time dimension-construction link dimension three-dimensional technical action evaluation system and a comprehensive construction stage management action system. The evaluation method is action staged evaluation method which can evaluate all process actions in the construction of the smart grid construction. With the adoption of the evaluation index system and evaluation method, the defects of poor comprehensiveness, small applicable scope and small precision in the prior art can be overcome, and the advantages of high comprehensiveness, wide applicable scope and high precision can be realized.