Microgrid (MG) can coordinate the dispatch of distributed generation,energy storage devices and loads to maximize the use of renewable energy. In this paper,the energy trading method among MGs is studied. Aiming at the dynamic stochastic factors of MG,a multi-time-scale method is adopted,including daily scheduling and intraday optimization,and the energy management framework of MG is proposed. Then,the energy management model of MG is established,including the daily scheduling model and the intraday optimization model,and the objective functions and constraint conditions are determined. Particle swarm algorithm is used to achieve the lowest economic cost and improve the economic performance of MGs. The proposed dynamic stochastic model,energy trading method and energy management model are verified and analyzed by taking three MGs as examples. The simulation results show that the proposed energy trading method can effectively improve the economy and reliability of the multi-microgrids.