Micro-grid plays an important role in improving the management efficiency of distributed renewable power and various loads in distribution power grid of new-type power system. Taking into account the efficiency problem of operational strategy caused by system prediction errors of micro-grid

this paper studies the policy improvement method of micro-grid operation strategy with electric vehicle loads. The structure of micro-grid with electric vehicle loads is discussed. Then a policy improvement method based on day-ahead optimized operation strategy is proposed. The day-ahead policy is further improved when approaching decision time using simulation based policy improvement method with updated system observation information. Simulation experiments are conducted to verify and demonstrate that the proposed policy improvement method can effectively improve the operational efficiency and economy of the micro-grid.