In order to improve the rapidity of power system fault analysis and processing, this paper introduces a kind of fault identification method based on the real-time substation graph mapping, with which fault wave record and protection information can automatically upload and fault current vector can be calculated in real time through the general information unified modeling station equipment and mapping technology. The fault vector analysis diagnosis method provides an effective tool for fault location and accurate evaluation of protection operation. Example analysis shows that each gap unit fault data can be shown in a visual unity and fault location and fault type can be identified quickly and accurately. This system provides a much-needed decision support in several fault handling of the large-scale power grid.