The invention relates to a fragmentation processing method of power grid simulating calculation data. Power grid data comprises grid rack structure data, equipment model parameter data and power grid operation data. The method comprises a fragmentation information forming process and a fragmentation information loading process, wherein the fragmentation information forming process comprises the following steps: determining a station as a center station; determining neighboring station data sets; traversing the neighboring station data sets; and storing formed fragmentation information into a fragmentation information table. The fragmentation information loading process comprises the following steps: obtaining the central longitude and latitude values of a regional center; determining the station which is nearest to the longitude and latitude values of the center; reading the fragmentation information table of the station; loading corresponding fragmentation information; judging whether the coverage rate of all loaded station coverage display areas satisfies requirements or not; if the coverage rate satisfies the requirements, exiting; and otherwise, carrying out iteration loading fragmentation information processing. The problems of shortage in hardware resources and low processing efficiency due to whole-grid data processing are solved.