The development of Smart Gird has higher demand on the support of electric power telecommunication network. Considering the “strong smart Grid construction and development mode, service modeling, bandwidth prediction and plan technology of electric power telecommunication network which covers the main parts of smart grid (Generation, Transmission and Power Dispatching) is studied in this paper. Then methods of service modeling of smart grid telecommunication network and backbone network bandwidth prediction method based on service models are carried out. It is proved that the model and method is strongly operational and practical according to the calculated result. The bandwidth calculated satisfies the development of telecommunication services. The method carried out in this paper that has already used in the “the 12th five year plan” of state grid telecommunication will do great help for the bandwidth management and plan of power system telecommunication network.