The utility model relates to a process layer network communication simulation system of an intelligent transformer station based on an EPON, and belongs to the technical field of a relay protection automation field in the electric power project field. The simulation system comprises transformer station process layer intelligent devices, ONU devices, an optical splitter, an OLT device, a simulation analysis master station, a message recorder and a message analysis device. Each transformer station process layer device is connected with an EPON access device. The EPON access device is connected with the EPON core device through the optical splitter. The transformer station process layer intelligent devices acquire information, and the information is transmitted to the simulation analysis master station and the message recorder through the EPON to record key communication performance indexes such as SV uniformity and GOOSE time delay, and integrated and graphical simulation analysis is provided.