The invention provides a graph splicing method for achieving layering display of an electric grid structure. The method includes the following steps that graph data of all units are extracted; the graph data are converted into a CIM-G format, guided into a setting calculating data center and spliced into a whole-network graph model; the whole-network graph model is processed in a layering mode. According to the graph splicing method for achieving layering display of the electric grid structure, the inherent graph data in electric grid models of all the units are taken as the basis, the graph data of all the units are spliced onto one picture, and the formed whole-network graph model is processed in the layering mode. The relationships between a hierarchical structure and all layers of structures of an electric grid can be clearly observed through layering displaying, and circuit structures belonging to all corresponding areas can be fast found by all the areas. The graph-based setting calculating work is finished, and the setting calculating efficiency is improved.