Wind power generations are widely used in power system as a type of clean renewable energy. However, the random fluctuation of wind power output has a negative effect on the power quality of power system. The energy storage system has been applied to suppress the voltage and power fluctuation by wind power access to power system because of its flexible bidirectional regulation ability. In this paper,a multi-objective energy storage optimal allocation model is established based on system voltage deviation,daily active power loss and total energy storage access capacity as the objective function. A beetle antennae search-improved multi-objective particle swarm optimization (BAS-IMOPSO) algorithm which is formed by combining BAS and IMOPSO is used to solve the model,and the optimal energy storage allocation scheme is selected in Pareto solution set by using the technique of order preference by similarity to ideal solution based on information entropy. The proposed model has been applied to IEEE 33-node distribution system. The simulation results show that the energy storage system optimized by BAS-IMOPSO algorithm has significantly higher ability to reduce voltage deviation and active power loss of distribution network than MOPSO algorithm does,and it can effectively improve the power quality with the ability of peak load shifting. The model shows the effectiveness of the proposed BAS-IMOPSO algorithm.