The invention provides a micro-grid energy storage system applied in an island far away from a land. The micro-grid energy storage system comprises a power demand module, an information processing module, a power distribution module, a real-time monitoring module and an energy module, wherein the power demand module is configured to send a signal of demand of an electrical load on power; the information processing module is configured to analyze, calculate and process the power demand signal and send the power demand signal to the power distribution module; the power distribution module is configured to distribute processed information and judge whether a storage battery energy storage module is connected or not; a distributed power module is configured to realize wind energy power generation and light energy power generation; the storage battery energy storage module is configured to supply electrical energy when the electricity generated by wind energy and light energy is deficient and meet a power load demand; and the real-time monitoring module is configured to monitor the information of temperature, electric quantity and duration of flight of the energy module, wherein an alarm system is arranged in the real-time monitoring module, and alarming and cutting off are performed if some index is unqualified. The system can be used for adjusting and outputting energy according to a real-time demand, and the energy can be utilized more effectively.