Abstract: The energy storage system is an indispensable component of the Mircogrid. It can be used to satisfy power quality requirement, to provide urgent power supply and suppress power fluctuation of renewable power generation. This paper focuses on the power sharing problem between energy-density and power-density components of the hybrid energy storage system (HESS). A hierarchical power allocation strategy is proposed to optimize the response frequency as well as state-of-charge (SOC) of supercapacitors. The simulation results proved the effectiveness of the proposed approaches.