Abstract: For the problems of traditional Buck-Boost converter including limited output voltage and poor stability, and the adjustable duty cycle range is insufficient, a new Buck-Boost converter topology is proposed. The working process of the converter is analyzed, the output-input voltage relationship of the converter and the voltage stress expression of the capacitor are derived. Compared with the traditional Buck-Boost converter, the new converter can achieve better voltage reduction effect when working in a more reasonable duty cycle range. The simulation results verify the correctness of theoretical analysis, and the experimental results show that the new Buck-Boost converter is feasible.