An operation mode for battery swap station(BSS) of electric vehicles based on the microgrid is proposed and a charging and discharging model of BSS is developed. According to the constraints of charging and discharging device battery and battery pack in BSS, a new optimal dispatching strategy for the microgrid containing BSS, wind generators, photovoltaic systems, fuel cells, microturbines and diesel generators is given. The economic indices of the BSS mode are compared with those of the traditional energy storage station(ESS) mode, and the simulation results show that BSS can bring more benefits than ESS. Furthermore, the economic impact of battery renting market capacity, the price of batteries and penetration of renewable energy are also discussed. The incentive indices proposed can provide a reference for the pricing of battery swap and renting.