The invention relates to an electric power GIS secondary development platform, which is designed layer by layer. The secondary development platform comprises a base GIS interface layer, an electric power GIS supporting layer and an electric GIS application layer from bottom to top. The base GIS interface layer comprises a serial base GIS vector data access, amendment and spatial analysis application interface method used for providing a computational analysis method for various images and providing geometric object model and image representation and topology model service specially used for an electric power system for the electric power GIS supporting layer. The electric power GIS supporting layer comprises an electric power object component library, an electric power object behavior library and an electric network modeling module; the electric network modeling module is used for transferring electric power object and electric power object behavior in the electric power object component library and the electric power object behavior library to provide electric network modeling service. The invention has the advantages that the development platform is fully suitable for the demands of the electric power system and easy to maintain, has good expansibility and insertable property and can be butted with various universal base GIS platforms.