Aiming at the issue of high reflux power in the three-level hybrid full-bridge bidirectional DC-DC converter, this paper proposes a reflux power optimization control strategy based on double phase-shift control with the objective of minimizing the reflux power. Firstly, the mathematical model of the three-level hybrid fullbridge DC-DC converter is established, and the characteristic relationship between the converter′s reflux power and transmission power is analyzed; then, taking the reflux power as the objective function, the equation and inequality constraints of different modes are converted into the constraint function by the KKT conditional method, and the Lagrange polynomial functions are constructed to find the optimal combination of the shift ratio; finally, in order to improve the rapidity of the system dynamic response, the direct power control method in the loop is adopted to realize the dynamic response of the converter in the face of unexpected situations. The simulation results demonstrate that the improved control strategy proposed in this paper can effectively reduce the reflux power and improve the dynamic response performance of the system when the input voltage and load change.