The invention discloses a low-loss rectifying circuit. The low-loss rectifying circuit comprises a first diode, a second diode, a third diode and a fourth diode and further comprises four MOSFETs correspondingly connected with the four diodes in parallel, and a logic control module. The logic control module comprises a signal voltage divider, a comparison circuit, an inverter and a three-state gate. The logic control module controls connection and disconnection of the MOSFETs to enable the MOSFETs to replace the diodes correspondingly connected with the MOSFETs in parallel to serve as a channel for a rectification exchange signal under the connection state. According to the low-loss rectifying circuit, the rectifying circuit has extremely low rectification voltage drop, and the loss of the rectifying circuit can be effectively reduced.