In recent years, with the development of power electronics related technology and the continuous derivation of circuit topology, Bidirectional DC-DC converter topology has been produced. It can realize the two-way flow of energy. It has the advantages of small volume, low cost, high efficiency and good dynamic performance. It has a very wide range of application scenarios in the fields of electric vehicles and photovoltaic power generation systems. However, due to the difference of parasitic parameters between phases, the current of each phase is unbalanced. Therefore, starting from the actual demand, a three-phase staggered parallel Bidirectional DC-DC converter is designed, and its current sharing causes and suppression methods are deeply studied to solve the problems existing in the traditional converter.