Given the features of each distributed power in the microgrid and the purpose of maximizing the advantages of the techiques of distributed generation which are shown in the aspects of economy, environment and energy, after meeting the constraints from the system, this paper proposes an economic dispatching model of the multi-objective microgrid which is an integrated consideration of the running costs, voltage bias and the capability of cutting the summit and filling the peak valley of the microgrid. Meanwhile, it’s easy to sink into the shortage of partial optimization while coping with the issue of optimization when the calculation of PSO is adopted, in order to avoid this shortage this paper proposes PSO-BF to solve the problem of optimal dispatch in the microgrid. Moreover, the emulating results show that the calculation of PSO-BF has the features of the whole and partial searching capabilities, fast convergence and high accuracy.