To improve the stability performance of a three-level Buck converter，a precise feedback decoupling control strategy based on a pre-filter is proposed.The mathematical model of the three-level Buck converter is established，and the reversibility analysis of the model is carried out based on the inverse system theory.The original model is linearly decoupled into two pseudolinear subsystems.The proportional-integral controller and the optimal controller are designed for the two subsystems，respectively to improve the performance of the system and suppress the influence of external disturbances on the system.Then，the pre-filter is designed to eliminate the adverse effects of the closed-loop zero point.Simulation and experimental results show that compared with the existing control methods，the proposed control strategy has faster response speed，better stability，and stronger robustness.