Abstract: Power system is becoming larger and larger,and the operation adjustment is more and more frequent,which puts higher requirements on the real-time performance of analysis and calculation. The graph database is a new database that originated from the parallel processing of massive data in internet. The data model can visually express the topology of the grid and easily realize parallel traversal query. Firstly,the characteristics of graph database are introduced from the aspects of data model and data query,and the potential advantages of its application in large-scale power system analysis and calculation are analyzed. Secondly,oriented to the criteria for integrity,consistency and efficiency,a power grid model design method based on graph datebase and following CIM/E standard is developed. Finally,based on graph database model of power grid,a parallel power grid topology analysis algorithm is implemented. The calculation results of the actual large-scale provincial power grid show that the proposed method can significantly improve the topology search efficiency.