Abstract: In this paper, a distributed energy storage system in DC micro-grid is investigated and a hierarchical power sharing control strategy based on discrete consensus algorithm is proposed. First, the power output capacity and equivalent SOC evaluation criteria of the asymmetric energy storage units are given. Based on these criteria, dynamic droop control is proposed to allocate the output power of each energy storage unit at the bottom layer. At the same time, considering the weak communication in distributed energy storage system, discrete consensus algorithm is used in the upper layer to dynamically adjust output power of energy storage units in order to reduce the SOC difference between energy storage units. Finally, a simulation model is built in Matlab/Simulink to verify the theoretical analysis. It is proved that the proposed method can achieve the optimal distribution of power in distributed energy storage system.