The invention relates to an economic subsidy standard determining method for providing standby power generation for an energy storage system, and the method comprises the following steps: calculating yearly benefit, obtained when a power supply company dispatches stored energy for standby use, in a power distribution network; determining the price paid for the energy storage system by the power supply company; calculating the yearly expense and income of the energy storage system; and determining an economic subsidy standard which is provided by a government for the energy storage system. The method aims at designing the economic subsidy mechanism which is provided by the government for the energy storage system, so as to guarantee that the energy storage system can obtain benefits for operation under the development level of the conventional energy storage technology, improve the market competiveness of the energy storage system, and motivate an independent investor to invest energy storage construction.