In this paper, an improved current-doubler rectifier with coupled inductors is proposed, which can extend duty ratio to reduce the peak current through the isolation transformer and to lower output current ripple. Additionally, passive lossless snubbers are introduced to reduce reverse recovery loss and clamp the voltage spike across the rectifier diodes. In this study, a 500 W prototype with a full-bridge phase-shift converter, the proposed rectifier, input voltage of 400 V and output voltage of 12 V was built, from which experimental measurements have shown that the efficiency can reach as high as 92% under full load condition