The invention relates to a method for generating an SSD file of a transformer substation. The method comprises the following steps: exhausting all main wiring modes of the transformer substation and aplurality of pieces of interval information corresponding to each main wiring mode; constructing an interval instance model file according to all main wiring modes of the transformer substation and aplurality of pieces of interval information corresponding to each main wiring mode; wherein each interval instance model file is determined according to the interval type, the maximization equipmentof the interval and the main wiring mode of the interval; and obtaining a main wiring mode of the transformer substation of which the SSD file is to be generated and related interval equipment, searching a plurality of corresponding interval instance model files according to the main wiring mode, and performing modification on the basis of the searched interval instance model files according to the interval equipment so as to generate the SSD file. According to the SSD file generation method, only the interval instance model file generated in advance needs to be modified, the position and associated attributes of each equipment primitive do not need to be concerned, and the SSD file generation efficiency is effectively improved.