In this paper, a PWM positive buck-boost converter with the reduced switching loss employing the quasi-resonant operation is proposed. Since the proposed converter utilizes resonance between a resonant inductor and a resonant capacitor, the switching loss and filter inductor size can be reduced. Moreover, the proposed converter shows the positive polarity output voltage configuration compared with the buck-boost converter. The operational principle and theoretical analysis are presented. To confirm the performance of the proposed converter, experimental results from a 24 V to 66 V, 100 kHz prototype are presented.