To solve the problem of unstable operation caused by capacity limitation of microgrid storage system, this paper presents an improved microgrid cooperative control strategy, of which the structure is double-layer of cooperative control, that is the primary control is the battery energy storage system and the secondary control is a microgrid management system (MMS). The primary control ensures that the frequency of the microgrid is within the acceptable range, while the secondary control ensures the largest spare capacity in the microgrid. To accurately describe the different types of distributed power of the prime mover to affect the microgrid system, by using detailed micro-source model, a microgrid simulation system is established and simulated. The simulation results show that the cooperative control strategy has a good dynamic performance, and ensures the quality of power supply requirements. Therefore the cooperative control strategy of microgrid has a better application prospects.