In the era of low-carbon economy, the traditional electric power industry will be confronted with tremendous changes on its external environment and internal developing model. The electric power industry should also pay closer attention to low-carbon, energy-saving as well as the emission of the CO2, SO2, NOX, and dust in the operation of power system, except of the safety and economy. In addition, technical characteristics and large-scale using of all kinds of energy-saving and low emission power which may have effects on the operation of power system should be analyzed. Furthermore, "The power dispatching and trading method oriented to low-carbon economy", which is more scientific and efficient, should be applied in the electric power industry. Power dispatching facing low-carbon economy is proposed and the objective function, constraint condition and transaction mechanism about the power dispatching are also studied in this paper.