Aiming at the problem of selecting the digital archive system in the power enterprise, combined with the three main decision goals, the paper establishes an index system from analyzing the internal and external environments. Then a real-word example Huaneng Dalian Power Plant demonstrates the feasibility of the proposed improved balancing and ranking method. The study shows that the proposed method can well handle the problem of index weight and index value, besides, each step is fact-based and easily to be understood and accepted by all parties. The implementation results and user feedback indicated that the selected system could solve the problems existing in the archival work and users were highly satisfied with the system and the provider. The study also has certain reference value for the similar applying.