Abstract: Embodiments of the present application provide a control method and a control device of an energy storage system. The energy storage system is coupled to an energy generation system and a power grid. The energy storage system includes a plurality of energy storage units. The method includes: acquiring discharging power information of the energy generation system, charging power information of the power grid and state information of the energy storage system, the state information of the energy storage system including time information of the energy storage units in a preset depth of discharge (DOD) interval; and determining an energy management strategy of the energy storage system according to the discharging power information of the energy generation system, the charging power information of the power grid and the state information of the energy storage system.